I did a job today that got me thinking about something Ive seen in the past. From time to time I will have a job that has the signs of an electrical fire. The customer will complaint will be no power or a burnt smell in the coach. Do not take this lightly. What I have found is when manufacturers use the very stiff romex style wiring is that the vibration of normal travel is causing the screw clamp in transfer switches to loosen. This causes arcing and sparks. This is a big fire hazard, so if you have funny electrical happenings or you smell burnt electrical smoke. Call a service center as soon as possible. A fire can consume an RV very fast. I want you all safe and sound.
Shawn
Monday, February 6, 2012
Sunday, December 18, 2011
Tuesday, December 13, 2011
RV Terminology
Airstreaming: using an Airstream travel trailer as RV of preference. Towing an Airstream travel trailer.
Arctic package: an RV that has been equipped with extra insulation and heat pads for holding tanks for winter time use.
Axle Lock: a replacement right front axle built to freel wheel the front wheel when towing (on towed car).
Back-up monitor: video camera mounted on rear of motorhome to assist the driver visually with backing up the motorhome, via a monitor mounted in the driver's compartment or in a central area of the cab where it can be viewed by the driver from the driver's seat. These monitors are usually left in the 'on' position to also assist the driver with the flow of traffic behind the motorhome and in watching a "towed" vehicle.
Basement: referring to storage area accessible from the outside, usually from the door threshold area down.
Black tank: holding tank of RV for storing toilet waste.
Blueboy/Blue-Boy: term for portable waste holding tank, often this plastic tank comes in a bright shade of blue, hence the term.
Boondocking/Boon-Docking: Also known as "dry camping" and "primitive camping", camping without using the modern conveniences of hooking up to electric, sewer or water. Term also implied for folks staying at a campground, but due to short length of stay, do not hook-up to the utilities even though these utilities are provided. See also: Boondocking, Boondocking Suite 101, Movin' On-View from the Driver's Seat, Roundtable Discussion on Boon-docking
Bowtie: reference to Chevrolet because of the "bowtie" trademark. See also: Chevrolet Trucks
Box: reference to motorhome's "living space" on a class A, built from the chassis up.
Braking system: referring to a brake system for a "towed" vehicle. Required in many states and Canadian provinces and definitely an add-on safety feature.
Break-away system: referring to a system that allows the "towed" vehicle to 'break-away' from the towing vehicle in the event of accident, an add-on safety feature.
Bubble: loose term for defining a variety of conditions; such as when describing the level of RV sitting. (example: my RV is 'off-level' a half bubble; referring to a 'bubble-leveler' tool). Can also be used to desribe a delamination condition. (See delamination definition listing), and can also be used to describe a condition on a rubber roof.
Bumper-Pull: slang term regarding the hitch or towing method for a conventional travel trailer or popup; receiver and ball-mount type hitch.
Bump Steer: a term used to describe a condition where the front axle feels to be rapidly bottoming out on the jounce bumpers and transferred back through the steering column and steering wheel. There can be several different causes to the problem with different cures for each condition. Sometimes a simple fix such as shocks or a steering stabilizer; sometimes more detailed corrections needed for correcting serious manufacturing oversights.
Caravan: a group of RVers traveling together with their various RVs. Large caravans often space RVs five minutes or so apart with CB radios used for communication between the various RVers. The end vehicle is sometimes called the "tailgunner" and is the occupants watch out for a caravan member that may have had road trouble in order to assist however possible.
Chassis Battery: battery in motorhome for operating 12 volt components of drivetrain.
Class A: class of motorhome referring to motorhome (box) built on chassis frame up.
Class B: class of motorhome referring to conversion vans.
Class C: class of motorhome referring to RV built using van-type chassis and cab.
Delam/Delamination: a term for the seperation of the paneling of Filon
and luan constructing a fiberglass sidewall of a RV. Usually caused by waterleaks and gives the exterior fiberglass skin a 'wavy' or 'bubbled' appearance. Depending on the size of the delamination, can typically be an expensive repair. See also: definition of Filon and definition of luan.
Diesel Puller: term for front engine diesel motorhome.
Diesel Pusher: term for rear engine diesel motorhome.
Dinghy: term for "towed vehicle", also known as "toad".
Dry Camping: also known as "boondocking" or "primitive camping", camping without hooking up to modern utilities as such provided at most campgrounds: water, septic/sewer and electricity. See also: Boondocking definition.
Dry Weight: weight of RV without adding fluids in storage holding tanks or by loading personal effects. See also term for "wet weight".
Dump station: place where holding tanks can be emptied either by paying a small fee or free.
Filon(registered trademark of Kemlite Company): fiberglass sheeting used in RVs with fiberglass sidewall construction. For additional information about fiberglass sidewalls visit http://www.filon.com
Fiver: other name for fifth wheel.
Flat tow: slang for towing a vehicle with all four wheels down on the ground.
FMCA: abbreviation for Family Motor Coach Association. See also: FMCA
Fresh tank: holding tank on RV for storing fresh water.
Full hookup: term for campground accomadations offerering water, sewer/septic and electricity; also refers to a RV with the abilities to use 'full-hookups'.
Fulltimer/Full-timer: someone who travels/lives in a recreational vehicle most of the year.
Gas Pusher: slang for rear gasoline engine mounted chassis on motorhome
Gear Vendor: brand name for an auxiliary transmission designed to give the driver control of the vehicle's gear ratio and being able to split gears for peak performance and at the same time have an overdrive.
Genset: abbreviation for generator set
Grey tank: holding tank of RV for storing used dishwater/bathing water.
GAWR: Abbreviation for Gross Axle Weight Rating. The maximum allowable weight each axle is designed to carry, as measured at the tires, therefore including the weight of the axle assembly itself. GAWR is established by considering the rating of each of its components (tires, wheels, springs, axle) and rating the axle on its weakest link. The GAWR assumes that the load is equal on each side. See also "Weights"
GCWR: Abbreviation for Gross Combined Weight Rating. The maximum allowable combined weight of the tow vehicle and the attached towed vehicle. GCWR assumes both vehicles has functioning brakes, with exceptions in some cases for very light towed vehicles, normally less than 1, 500 pounds. (check your chassis manual or towing guide) See also "Weights"
GVWR: Abbreviation for Gross Vehicle Weight Rating. The maximum allowable weight of the fully loaded vehicle, including liquids, passengers, cargo, and tongue weight of any towed vehicle. See also "Weights"
HP: Abbreivation for "horse power".
HR: Abbreviation for Holiday Rambler, a well-known RV manufacturer. See Also: Holiday Rambler
House Battery: battery or batteries in motorhome for operating the 12 volt system within the motorhome, seperate from the chassis.
Hula skirt: term used for a type of dirt skirt accessory some RVers use on the back of their motorhome to aid in the protection from debris thrown from their rear wheels to the vehicles directly behind them or being towed behind them. This dirt skirt is usually the length of the rear bumper and resembles a 'short' version of a Hawaiian 'hula-skirt', hence the term.
Hybrid: term for fifth wheel or travel trailer that has been manufactured to ge "different" than the standard interior living box. Usually by having popout ends over bedrooms that give a "tent" like area for sleeping.
Jackknife: 90% angle obtained from turning/backing fifth wheel or travel trailer with tow vehicle. Jackknifing a short bed truck towing a fifth wheel without the use of a slider hitch or extended fifth wheel pin box can result in damage to the truck cab or breaking out the back window of the truck cab from the truck and fifth wheel "colliding".
LP: propane; abbreviation for liquefied petroleum gas, which is a gas liquefied by compression, consisting of flamable hydrocarbons and obtained as a by-product from the refining of petroleum or natural gas. Also called bottled gas, LPG (liquid petroleum gas) and CPG (compressed petroleum gas).
Luan: the 1/8" backing board for filon (the fiberglass sheeting use in RVs with fiberglass construction). Luan is the 'base' the filon (fiberglass) is glued on to.
MH: abbreviation for "motorhome".
Minnie Winnie: a brand model of Winnebago.
Motorcoach: term for motorhome on "bus-type" chassis.
NADA: abbreviation for National Automotive Dealer's Association. See Also: NADA
NCC: abbreviation for Net Carrying Capacity. The maximum weight of all personal belongings, occupants, food, fresh water, LP gas, tools, dealer installed accessories, etc., that can be carried by the RV (Technically, the GVWR less the UVW equals the NCC). See also "weights"
OEM: abbreviation for "original equipment manufacturer".
Park Model: Type of RV that is usually designed for permanent parking but is shorter in length than a traditional mobile home. All the amenities of a mobile home but not built for recreational travel.
Part-timers: People who use their RV for longer than normal vacation time but less than one year.
Patio mat: Carpet or woven mat for use on ground outside of RV. Used whether or not a concrete patio pad is available where camping.
Pitch-in: Term for a RV campground "get-together", usually means "pitching-in" a covered dish or casserole.
PO: Abbreviation for "pop-up" camper.
Pop-out: Term for room or area that 'pops-out' for additional living space in RV. This type of expanded living area was more common before the technology of slide-out rooms became popular and available.
Popup/Pop-Up: Folding camping trailer. See also: Internet Popup Newsgroup
Porpoising: A term used to define an up and down motion with a RV.
Primitive camping: Also known as "dry camping", boondocking. Camping without the modern convenience of full-hookup facilities of city/well water, sewer/septic and electricity. Primitive campers rely on 'on-board' systems for these conveniences; generator, batteries, stored water, etc.
Puller: Slang for front engine motorhome. Term most often used to refer to front mounted diesel engine motorhomes.
Pull-through: Term for a camping space (whether in campground or not) that only requires the driver to "pull-through" or "drive-through" to access the camping spot, and upon leaving (after camping) you again just drive forward to leave or exit the camping space.
Pusher: Slang for rear engine motorhome. Term most often used to refer to diesel engine motorhomes.
UVW: Abbreviation for Unloaded Vehicle Weight. The weight of a vehicle as built at the factory with full fuel, engine (generator) oil and coolants. It does not inlude cargo, fresh water, LP gas, occupants or dealer installed accessories. See also "weights" (below).
Wally World: slang term used by RVers to describe a Walmart. See also: Walmart
Weekender's: people who own their RV's for weekend and vacation use.
Wet Weight: termed used by RVers to describe the weight of a RV with all storage and holding tanks full., i.e., water, propane, etc. See also term: "dry weight"
Wide-body: a RV that has a width exceeding eight feet. See also: U.S. Motorhome Regulations, U.S. Towing and Road Laws (travel trailers and fifth wheels) or RV Travel Guide
Winnie: nickname for Winnebago, a well-known RV manufacturer. See also: Winnebago Industries
Arctic package: an RV that has been equipped with extra insulation and heat pads for holding tanks for winter time use.
Axle Lock: a replacement right front axle built to freel wheel the front wheel when towing (on towed car).
Back-up monitor: video camera mounted on rear of motorhome to assist the driver visually with backing up the motorhome, via a monitor mounted in the driver's compartment or in a central area of the cab where it can be viewed by the driver from the driver's seat. These monitors are usually left in the 'on' position to also assist the driver with the flow of traffic behind the motorhome and in watching a "towed" vehicle.
Basement: referring to storage area accessible from the outside, usually from the door threshold area down.
Black tank: holding tank of RV for storing toilet waste.
Blueboy/Blue-Boy: term for portable waste holding tank, often this plastic tank comes in a bright shade of blue, hence the term.
Boondocking/Boon-Docking: Also known as "dry camping" and "primitive camping", camping without using the modern conveniences of hooking up to electric, sewer or water. Term also implied for folks staying at a campground, but due to short length of stay, do not hook-up to the utilities even though these utilities are provided. See also: Boondocking, Boondocking Suite 101, Movin' On-View from the Driver's Seat, Roundtable Discussion on Boon-docking
Bowtie: reference to Chevrolet because of the "bowtie" trademark. See also: Chevrolet Trucks
Box: reference to motorhome's "living space" on a class A, built from the chassis up.
Braking system: referring to a brake system for a "towed" vehicle. Required in many states and Canadian provinces and definitely an add-on safety feature.
Break-away system: referring to a system that allows the "towed" vehicle to 'break-away' from the towing vehicle in the event of accident, an add-on safety feature.
Bubble: loose term for defining a variety of conditions; such as when describing the level of RV sitting. (example: my RV is 'off-level' a half bubble; referring to a 'bubble-leveler' tool). Can also be used to desribe a delamination condition. (See delamination definition listing), and can also be used to describe a condition on a rubber roof.
Bumper-Pull: slang term regarding the hitch or towing method for a conventional travel trailer or popup; receiver and ball-mount type hitch.
Bump Steer: a term used to describe a condition where the front axle feels to be rapidly bottoming out on the jounce bumpers and transferred back through the steering column and steering wheel. There can be several different causes to the problem with different cures for each condition. Sometimes a simple fix such as shocks or a steering stabilizer; sometimes more detailed corrections needed for correcting serious manufacturing oversights.
Caravan: a group of RVers traveling together with their various RVs. Large caravans often space RVs five minutes or so apart with CB radios used for communication between the various RVers. The end vehicle is sometimes called the "tailgunner" and is the occupants watch out for a caravan member that may have had road trouble in order to assist however possible.
Chassis Battery: battery in motorhome for operating 12 volt components of drivetrain.
Class A: class of motorhome referring to motorhome (box) built on chassis frame up.
Class B: class of motorhome referring to conversion vans.
Class C: class of motorhome referring to RV built using van-type chassis and cab.
Delam/Delamination: a term for the seperation of the paneling of Filon
and luan constructing a fiberglass sidewall of a RV. Usually caused by waterleaks and gives the exterior fiberglass skin a 'wavy' or 'bubbled' appearance. Depending on the size of the delamination, can typically be an expensive repair. See also: definition of Filon and definition of luan.Diesel Puller: term for front engine diesel motorhome.
Diesel Pusher: term for rear engine diesel motorhome.
Dinghy: term for "towed vehicle", also known as "toad".
Dry Camping: also known as "boondocking" or "primitive camping", camping without hooking up to modern utilities as such provided at most campgrounds: water, septic/sewer and electricity. See also: Boondocking definition.
Dry Weight: weight of RV without adding fluids in storage holding tanks or by loading personal effects. See also term for "wet weight".
Dump station: place where holding tanks can be emptied either by paying a small fee or free.
Filon
(registered trademark of Kemlite Company): fiberglass sheeting used in RVs with fiberglass sidewall construction. For additional information about fiberglass sidewalls visit http://www.filon.comFiver: other name for fifth wheel.
Flat tow: slang for towing a vehicle with all four wheels down on the ground.
FMCA: abbreviation for Family Motor Coach Association. See also: FMCA
Fresh tank: holding tank on RV for storing fresh water.
Full hookup: term for campground accomadations offerering water, sewer/septic and electricity; also refers to a RV with the abilities to use 'full-hookups'.
Fulltimer/Full-timer: someone who travels/lives in a recreational vehicle most of the year.
Gas Pusher: slang for rear gasoline engine mounted chassis on motorhome
Gear Vendor: brand name for an auxiliary transmission designed to give the driver control of the vehicle's gear ratio and being able to split gears for peak performance and at the same time have an overdrive.
Genset: abbreviation for generator set
Grey tank: holding tank of RV for storing used dishwater/bathing water.
GAWR: Abbreviation for Gross Axle Weight Rating. The maximum allowable weight each axle is designed to carry, as measured at the tires, therefore including the weight of the axle assembly itself. GAWR is established by considering the rating of each of its components (tires, wheels, springs, axle) and rating the axle on its weakest link. The GAWR assumes that the load is equal on each side. See also "Weights"
GCWR: Abbreviation for Gross Combined Weight Rating. The maximum allowable combined weight of the tow vehicle and the attached towed vehicle. GCWR assumes both vehicles has functioning brakes, with exceptions in some cases for very light towed vehicles, normally less than 1, 500 pounds. (check your chassis manual or towing guide) See also "Weights"
GVWR: Abbreviation for Gross Vehicle Weight Rating. The maximum allowable weight of the fully loaded vehicle, including liquids, passengers, cargo, and tongue weight of any towed vehicle. See also "Weights"
HP: Abbreivation for "horse power".
HR: Abbreviation for Holiday Rambler, a well-known RV manufacturer. See Also: Holiday Rambler
House Battery: battery or batteries in motorhome for operating the 12 volt system within the motorhome, seperate from the chassis.
Hula skirt: term used for a type of dirt skirt accessory some RVers use on the back of their motorhome to aid in the protection from debris thrown from their rear wheels to the vehicles directly behind them or being towed behind them. This dirt skirt is usually the length of the rear bumper and resembles a 'short' version of a Hawaiian 'hula-skirt', hence the term.
Hybrid: term for fifth wheel or travel trailer that has been manufactured to ge "different" than the standard interior living box. Usually by having popout ends over bedrooms that give a "tent" like area for sleeping.
Jackknife: 90% angle obtained from turning/backing fifth wheel or travel trailer with tow vehicle. Jackknifing a short bed truck towing a fifth wheel without the use of a slider hitch or extended fifth wheel pin box can result in damage to the truck cab or breaking out the back window of the truck cab from the truck and fifth wheel "colliding".
LP: propane; abbreviation for liquefied petroleum gas, which is a gas liquefied by compression, consisting of flamable hydrocarbons and obtained as a by-product from the refining of petroleum or natural gas. Also called bottled gas, LPG (liquid petroleum gas) and CPG (compressed petroleum gas).
Luan: the 1/8" backing board for filon (the fiberglass sheeting use in RVs with fiberglass construction). Luan is the 'base' the filon (fiberglass) is glued on to.
MH: abbreviation for "motorhome".
Minnie Winnie: a brand model of Winnebago.
Motorcoach: term for motorhome on "bus-type" chassis.
NADA: abbreviation for National Automotive Dealer's Association. See Also: NADA
NCC: abbreviation for Net Carrying Capacity. The maximum weight of all personal belongings, occupants, food, fresh water, LP gas, tools, dealer installed accessories, etc., that can be carried by the RV (Technically, the GVWR less the UVW equals the NCC). See also "weights"
OEM: abbreviation for "original equipment manufacturer".
Park Model: Type of RV that is usually designed for permanent parking but is shorter in length than a traditional mobile home. All the amenities of a mobile home but not built for recreational travel.
Part-timers: People who use their RV for longer than normal vacation time but less than one year.
Patio mat: Carpet or woven mat for use on ground outside of RV. Used whether or not a concrete patio pad is available where camping.
Pitch-in: Term for a RV campground "get-together", usually means "pitching-in" a covered dish or casserole.
PO: Abbreviation for "pop-up" camper.
Pop-out: Term for room or area that 'pops-out' for additional living space in RV. This type of expanded living area was more common before the technology of slide-out rooms became popular and available.
Popup/Pop-Up: Folding camping trailer. See also: Internet Popup Newsgroup
Porpoising: A term used to define an up and down motion with a RV.
Primitive camping: Also known as "dry camping", boondocking. Camping without the modern convenience of full-hookup facilities of city/well water, sewer/septic and electricity. Primitive campers rely on 'on-board' systems for these conveniences; generator, batteries, stored water, etc.
Puller: Slang for front engine motorhome. Term most often used to refer to front mounted diesel engine motorhomes.
Pull-through: Term for a camping space (whether in campground or not) that only requires the driver to "pull-through" or "drive-through" to access the camping spot, and upon leaving (after camping) you again just drive forward to leave or exit the camping space.
Pusher: Slang for rear engine motorhome. Term most often used to refer to diesel engine motorhomes.
UVW: Abbreviation for Unloaded Vehicle Weight. The weight of a vehicle as built at the factory with full fuel, engine (generator) oil and coolants. It does not inlude cargo, fresh water, LP gas, occupants or dealer installed accessories. See also "weights" (below).
Wally World: slang term used by RVers to describe a Walmart. See also: Walmart
Weekender's: people who own their RV's for weekend and vacation use.
| Weights: |
| GAWR: Gross Axle Weight Rating. The maximum allowable weight each axle is designed to carry, as measured at the tires, therefore including the weight of the axle assembly itself. GAWR is established by considering the ratio of each of its components (tires, wheels, springs, axle) and rating the axle on its weakest link. The GAWR assumes that the load is equal on each side. |
| GCWR: Gross Combined Weight Rating. The maximim allowable combined weight of the tow vehicle and the attached towed vehicle. GCWR assumes both vehicles have functioning brakes, with exceptions in some cases for very light towed vehicles, normally less than 1,500 pounds. (check your chassis manual or towing guide). |
| GVWR: Gross Vehicle Weight Rating. The maximum allowable weight of the fully loaded vehicle, including liquids, passengers, cargo, and tongue weight of any towed vehicle. |
| NCC: Net Carrying Capacity. The maximum weight of all personal belongings, occupants, food, fresh water, LP gas, tools, dealer installed accessories, etc., that can be carried by the RV. (Technically, the GVWR less the UVW equals the NCC |
| UVW: Unloaded Vehicle Weight. The weight of a vehicle as built at the factory with full fuel, engine (generator) oil and coolants. It does not include cargo, fresh water, LP gas, occupants, or dealer installed accessories. |
| water (weight): 8.3 lbs. per gallon |
| lp gas (weight): 4.5 lbs. per gallon |
| driver (estimated weight): 200 lbs. |
| passenger (esttmated weight): 120 lbs. |
Wide-body: a RV that has a width exceeding eight feet. See also: U.S. Motorhome Regulations, U.S. Towing and Road Laws (travel trailers and fifth wheels) or RV Travel Guide
Winnie: nickname for Winnebago, a well-known RV manufacturer. See also: Winnebago Industries
RV CHASSIS
What's new in the field of motorhome chassis?
Newcomer Workhorse Custom Chassis (formerly General Motors) is changing the way people service their vehicles. The company offers consumers the ability to get their chassis, as well as their motorhome, serviced by the dealership (RV manufacturers and dealers must meet specific certification standards to be selected). This "one stop" method puts an end to customers' frustrations of running to different places to fix different components of their RV. This is already affecting the way others do business. I see Freightliner is running two shifts at most of their facilities and Cummins. Onan and Detroit Diesel and Allison are also starting extended service hours. In addition, the P-series chassis has always been a leader in coaches up to about 34 feet in length.
The Ford chassis is commonly used in coaches up to 37 feet but is extremely underpowered and overloaded when used for these larger motorhome designs, causing the end user to complain about low power and handling problems. Although the Triton V-10 is proving to be an exceptional engine and the new Ford Super Duty chassis is a very strong competitor, these bus-type Class A motorhomes in the 35-37 foot range are over-kill for a gasoline chassis.
What about diesels?
The range of diesel chassis has grown significantly over the past ten years for medium-priced motorhomes. The leaders, Freightliner, Spartan, Roadmaster, Magnum and Alpine Coach (in no particular order), have made a wider variety of options in Class A diesel motorhomes.
Upstart Alpine (Western Recreational Vehicles) designed their chassis with braking and handling as the main characteristics and have earned recognition for the superior handling brought on by the Toyo tires and i.P.d suspension products. They also were tested and rated on top of the industry by Bendix brakes (using a hydraulic braking system instead of the normal air brakes for a chassis this size).
I recommend 275 horse power for units up to 20,000 pounds GVWR; the 300-350 horse power will adequately power units up to around 26,000 GVWR. Your larger 40-42 foot motorhomes need the 400-500 horse power diesel engine for adequate performance.
For those interested in mini-motorhomes, what are the chassis options?
The Class C motorhome chassis is fairly simple since the choices are not near as broad as the Class A chassis market. Basically, there is Ford, Chevy and Dodge. Although there are a few Freightliner and others out there, these units normally are not in the same price range or ballpark as your other Class C motorhomes. These would be considered more of a "specialty" vehicle.
The Ford Super Duty chassis is by far the most popular in the Class C industry today, with options of the Triton V-10 or 7.3 liter Powerstroke diesel to power the Ford Super Duty chassis, Ford is able to offer the manufacturers a chassis able to handle $14,050 pounds GCWR, capable of powering some of the larger Class Cs on the market today.
General Motors offers both the Vortec 454 and 6.5 liter diesel for their Class C type chassis, but the GM diesel is much less popular in the industry. Dodge, on the other hand, offers the 360ci in the Class C model.
What is the most important part in deciding on the right chassis?
In all cases, weight distribution and weight capabilities will be the most important factor in your choice. Even though the chassis has weight ratings for the load, weight distribution is very critical on how the coach will handle. The rule of thumb is, if the overhang from the rear wheels to the rear bumper is excessive, you'll find the lighter the steering will feel on the road. Check the GVWR and GCWR to see how much weight you have left for a tow vehicle; and look to see if the overhang is going to cause consideration for air bags or heavy sway bars on the rear. Some coach builders add the air bags as standard equipment.
Class C chassis are heavy-duty van chassis and when the coach manufacturer constructs an excessively long body, it results in a long overhang behind the rear axle causing the handling to suffer. If the coach manufacturer cuts and stretches the frame rails between the axles, they can distribute the weight on springs more evenly for controlled handling. In other words, if they build it wide, high and long on a standard chassis, be ready to hang on and fight the road.
When it comes to Class A motorhomes and overhang, it really depends a lot on the chassis - whether it was built on a short wheel base chassis with manufactured long frame rails and springs to support the weight, or did the coach manufacturer extend the frame rails at the back to support the box?
If you see a greater than ten foot overhang from the rear axle to the back bumper, look at the frame rail and see if the coach manufacturer added frame rail extensions. You will only see this on gas or front diesel engine models. This same rule also applies to tag axles. Some manufacturers add a tag axle then stretch the frame at the back, leaving the coach with the same unstable handling.
Which is better for me, gas or diesel?
You might want to begin by first considering the maintenance needs for both gas and diesel engines. While a diesel unit normally gets better fuel mileage, the cost of service normally increases. The oil change service gas engine at 3,000 miles using seven quarts of oil will be far less expensive than the diesel at 5,000 miles requiring 20-40 quarts of oil. Lubrication intervals should be at 3,000 miles on both chassis and normal maintenance, i.e., brakes, differential, wheel bearings, etc., also have similar maintenance intervals.
As a rule, the larger the motorhome, the stronger the case becomes for a diesel engine; beyond the 35-foot range, front-mounted engines become impractical. Diesel pushers provide a quiet ride and plenty of power for larger vehicles. Newer entry-level diesel chassis are being produced by Spartan Motors.
What are some things I can do to get better handling?
A number of chassis manufacturers are using i.P.d. suspension as standard components and many RVers boast about their good handling. More and more folks are looking into i.P.d. to correct their handling problems.
Which is better, hydraulic or air brakes?
In my opinion, the hydraulic brakes are better than air brakes since the pads are locking on both sides of the rotor. What you end up with are more square inches of braking surface and superior cooling of the braking surface than with the drum brakes (air brakes use drums and shoes and require much more maintenance).
Both hydraulic and air brakes can fade from overheating, but more permanent damage can be caused to the drums and shoes in air brakes. Your average person looking at an RV has never been accustomed to air brakes and has little ideal of how they work and what effect low air pressure can have on the system. In a hydraulic system the front and rear system are separated and one should hold in the other fails. Alpine Coach put a lot of thought into building their chassis and safety was the reason for their hydraulic brakes. Safari also looked at both options and chose hydraulics when building their Magnum chassis.
What should I do to protect my chassis?
A few key points to look at in maintenance is rust lubrication. In the past, undercoating was done by specialty shops; now with the introduction of Amsoil's undercoat in spray bottles, the owner can now easily and efficiently fight rust while performing his/her normal chassis lubrication. Be sure to follow the directions explicitly. Take care to protect wiring harnesses, fuel lines and other components not compatible with undercoating products.
All fluid levels should be checked on a regular basis. The use of synthetic lubricants throughout the drivetrain can extend the normal maintenance intervals while adding extra protection and saving in the cost of yearly maintenance.
Be sure to look at all weather head electrical connections and seal with a spray protector to fight corrosion twice a year. Follow the owner's manual guidelines for regular maintenance that's beyond your capabilities.
When buying a used coach, what are some signs of chassis wear?
Inspect the chassis for excessive rust throughout the drivetrain and entire chassis. Check all fluid levels for irregular signs (i.e., color, smell, etc.), look for weak or sagging springs and check for fluid leaks. Inspect rubber hoses, bushings, belts and vacuum lines for weather cracking. Inspect tires for abnormal tread wear. Road test the motorhome for unusual noises, vibration, handling problems and other performance characteristics. Be sure all gauges and monitoring equipment is functioning properly. If in doubt, take along a trust mechanic or pay for a "Pre-Purchase" inspection by a professional.
Newcomer Workhorse Custom Chassis (formerly General Motors) is changing the way people service their vehicles. The company offers consumers the ability to get their chassis, as well as their motorhome, serviced by the dealership (RV manufacturers and dealers must meet specific certification standards to be selected). This "one stop" method puts an end to customers' frustrations of running to different places to fix different components of their RV. This is already affecting the way others do business. I see Freightliner is running two shifts at most of their facilities and Cummins. Onan and Detroit Diesel and Allison are also starting extended service hours. In addition, the P-series chassis has always been a leader in coaches up to about 34 feet in length.
The Ford chassis is commonly used in coaches up to 37 feet but is extremely underpowered and overloaded when used for these larger motorhome designs, causing the end user to complain about low power and handling problems. Although the Triton V-10 is proving to be an exceptional engine and the new Ford Super Duty chassis is a very strong competitor, these bus-type Class A motorhomes in the 35-37 foot range are over-kill for a gasoline chassis.
What about diesels?
The range of diesel chassis has grown significantly over the past ten years for medium-priced motorhomes. The leaders, Freightliner, Spartan, Roadmaster, Magnum and Alpine Coach (in no particular order), have made a wider variety of options in Class A diesel motorhomes.
Upstart Alpine (Western Recreational Vehicles) designed their chassis with braking and handling as the main characteristics and have earned recognition for the superior handling brought on by the Toyo tires and i.P.d suspension products. They also were tested and rated on top of the industry by Bendix brakes (using a hydraulic braking system instead of the normal air brakes for a chassis this size).
I recommend 275 horse power for units up to 20,000 pounds GVWR; the 300-350 horse power will adequately power units up to around 26,000 GVWR. Your larger 40-42 foot motorhomes need the 400-500 horse power diesel engine for adequate performance.
For those interested in mini-motorhomes, what are the chassis options?
The Class C motorhome chassis is fairly simple since the choices are not near as broad as the Class A chassis market. Basically, there is Ford, Chevy and Dodge. Although there are a few Freightliner and others out there, these units normally are not in the same price range or ballpark as your other Class C motorhomes. These would be considered more of a "specialty" vehicle.
The Ford Super Duty chassis is by far the most popular in the Class C industry today, with options of the Triton V-10 or 7.3 liter Powerstroke diesel to power the Ford Super Duty chassis, Ford is able to offer the manufacturers a chassis able to handle $14,050 pounds GCWR, capable of powering some of the larger Class Cs on the market today.
General Motors offers both the Vortec 454 and 6.5 liter diesel for their Class C type chassis, but the GM diesel is much less popular in the industry. Dodge, on the other hand, offers the 360ci in the Class C model.
What is the most important part in deciding on the right chassis?
In all cases, weight distribution and weight capabilities will be the most important factor in your choice. Even though the chassis has weight ratings for the load, weight distribution is very critical on how the coach will handle. The rule of thumb is, if the overhang from the rear wheels to the rear bumper is excessive, you'll find the lighter the steering will feel on the road. Check the GVWR and GCWR to see how much weight you have left for a tow vehicle; and look to see if the overhang is going to cause consideration for air bags or heavy sway bars on the rear. Some coach builders add the air bags as standard equipment.
Class C chassis are heavy-duty van chassis and when the coach manufacturer constructs an excessively long body, it results in a long overhang behind the rear axle causing the handling to suffer. If the coach manufacturer cuts and stretches the frame rails between the axles, they can distribute the weight on springs more evenly for controlled handling. In other words, if they build it wide, high and long on a standard chassis, be ready to hang on and fight the road.
When it comes to Class A motorhomes and overhang, it really depends a lot on the chassis - whether it was built on a short wheel base chassis with manufactured long frame rails and springs to support the weight, or did the coach manufacturer extend the frame rails at the back to support the box?
If you see a greater than ten foot overhang from the rear axle to the back bumper, look at the frame rail and see if the coach manufacturer added frame rail extensions. You will only see this on gas or front diesel engine models. This same rule also applies to tag axles. Some manufacturers add a tag axle then stretch the frame at the back, leaving the coach with the same unstable handling.
Which is better for me, gas or diesel?
You might want to begin by first considering the maintenance needs for both gas and diesel engines. While a diesel unit normally gets better fuel mileage, the cost of service normally increases. The oil change service gas engine at 3,000 miles using seven quarts of oil will be far less expensive than the diesel at 5,000 miles requiring 20-40 quarts of oil. Lubrication intervals should be at 3,000 miles on both chassis and normal maintenance, i.e., brakes, differential, wheel bearings, etc., also have similar maintenance intervals.
As a rule, the larger the motorhome, the stronger the case becomes for a diesel engine; beyond the 35-foot range, front-mounted engines become impractical. Diesel pushers provide a quiet ride and plenty of power for larger vehicles. Newer entry-level diesel chassis are being produced by Spartan Motors.
What are some things I can do to get better handling?
A number of chassis manufacturers are using i.P.d. suspension as standard components and many RVers boast about their good handling. More and more folks are looking into i.P.d. to correct their handling problems.
Which is better, hydraulic or air brakes?
In my opinion, the hydraulic brakes are better than air brakes since the pads are locking on both sides of the rotor. What you end up with are more square inches of braking surface and superior cooling of the braking surface than with the drum brakes (air brakes use drums and shoes and require much more maintenance).
Both hydraulic and air brakes can fade from overheating, but more permanent damage can be caused to the drums and shoes in air brakes. Your average person looking at an RV has never been accustomed to air brakes and has little ideal of how they work and what effect low air pressure can have on the system. In a hydraulic system the front and rear system are separated and one should hold in the other fails. Alpine Coach put a lot of thought into building their chassis and safety was the reason for their hydraulic brakes. Safari also looked at both options and chose hydraulics when building their Magnum chassis.
What should I do to protect my chassis?
A few key points to look at in maintenance is rust lubrication. In the past, undercoating was done by specialty shops; now with the introduction of Amsoil's undercoat in spray bottles, the owner can now easily and efficiently fight rust while performing his/her normal chassis lubrication. Be sure to follow the directions explicitly. Take care to protect wiring harnesses, fuel lines and other components not compatible with undercoating products.
All fluid levels should be checked on a regular basis. The use of synthetic lubricants throughout the drivetrain can extend the normal maintenance intervals while adding extra protection and saving in the cost of yearly maintenance.
Be sure to look at all weather head electrical connections and seal with a spray protector to fight corrosion twice a year. Follow the owner's manual guidelines for regular maintenance that's beyond your capabilities.
When buying a used coach, what are some signs of chassis wear?
Inspect the chassis for excessive rust throughout the drivetrain and entire chassis. Check all fluid levels for irregular signs (i.e., color, smell, etc.), look for weak or sagging springs and check for fluid leaks. Inspect rubber hoses, bushings, belts and vacuum lines for weather cracking. Inspect tires for abnormal tread wear. Road test the motorhome for unusual noises, vibration, handling problems and other performance characteristics. Be sure all gauges and monitoring equipment is functioning properly. If in doubt, take along a trust mechanic or pay for a "Pre-Purchase" inspection by a professional.
How to Get the Most from Your Recreational Vehicle Tires
The Importance of Air Pressure
The most important factor in maximizing the life of your tires is maintaining proper inflation. Driving on any tire that does not have the correct inflation pressure for the load of the vehicle is dangerous and may cause premature wear, tire damage, and/or loss of control of the vehicle.
A tire that is underinflated will build up excessive heat that may go beyond the prescribed limits of endurance of the rubber and the radial cords. This could result in sudden tire failure. A tire that is underinflated will also cause poor vehicle handling, rapid and/or irregular tire wear, and a decrease in its fuel economy.
Overinflation will reduce the tire's footprint or contact patch with the road, thus reducing the traction, braking capacity, and handling of the vehicle. A tire that is overinflated for the load that it is carrying will also contribute to a harsh ride, uneven tire wear, and will be susceptible to impact damage.
Maintaining correct tire inflation pressure for each loaded wheel position on your vehicle is of the utmost importance and must be a part of regular vehicle maintenance.
How Much Air Should I Carry in My Tires?
Federal law requires that the tire's maximum load rating be molded into the sidewall of the tire. On the tire's sidewall you can see the maximum load allowed for the size tire and load rating, and the minimum cold air inflation pressure needed to carry that stated maximum load. Utilizing less air pressure means a lesser load can be carried by the tire.
The amount of air pressure you need to use is dependent on the weight of your fully loaded vehicle.
It is important to note that the cold inflation pressure for the tire must never exceed the maximum inflation rating stamped on the wheel.
When Should I Check my RV's Tires' Air Pressure?
You should check the air pressure every two weeks or at least one a month and before any major trip. Your RV tires' air pressure should be checked every "drive" morning on long trips. On short trips of a day or less driving each way, your tires should be checked before you leave on your trip and again before you start your trip home. If your vehicle is stored for any length of time, air pressure should be checked prior to storage, but more importantly, when it comes out of storage.
Check your tires when they are "cold" and have not been driven for more than one mile. The stated load capacity for a given cold inflation pressure is based on ambient outside temperature. If you must check your tires when they are warm or hot, do allow for a slight increase in air pressure and make sure they are within a couple of pounds of each other on the same axle. Never let air out of a hot tire.
It is recommended you purchase a quality truck tire air gauge which has an angled dual head. This type of gauge allows you to check inflations on the inner dual wheel which has the valve stem pointing toward you, and on the outer wheel which has the valve stem pointing away from you. Nothing should restrict your ability to check a tire's air pressure daily when you are driving your RV. Pressure sealing valve caps should always be used to prevent air from escaping from the valve stem. If you use valve stem extension hoses, make sure they are good quality stainless steel braid reinforced and are securely anchored to the outer wheel. If your RV has wheel covers which must be removed to check the inflation, then consider removing them on a long trip, as the extra time and effort required may lead you to avoid checking your air pressure.
What if You Don't Check Your Air Pressure?
If a tire picks up a nail or screw that creates a slow leak and causes some air pressure loss, you might eventually spot it visually if it's a front tire. If it is an outside rear dual, you might also spot it with a visual inspection. However, if it is an inside rear dual, the chances of spotting it without an air pressure check are very slim. If you begin driving without finding it, very quickly (in most cases a few miles) your outside rear tire next to the low air pressure tire is going to heat up from carrying double its load, which will cause both tires to fail. Then you'll have two tires down on the same side and on the same axle, and a five ton or more vehicle at any speed is difficult to bring under control.
How to Determine Your RV's Correct Weight
The GVWR (Gross Vehicle Weight Rating) and GAWR (Gross Axle Weight Rating) stickers on your motorhome (normally located on the support pillar next to the driver's seat) will show you the chassis manufacturer's and/or the motorhome manufacturer's total vehicle maximum weight ratings and per axle weight rating.
The GVWR is the maximum total weight for which the vehicle is rated - including passengers, fluids, and cargo. The GAWR is the maximum for which a single axle is designed. These per axle and total maximum weight ratings could be limited by the tires, wheels, axle and axle bearings, springs, the vehicle frame, or other components of the vehicle.
The GAWR sticker is only a guide in knowing your maximum loaded axle weights and subsequently your correct tire inflation pressure. Every motorhome, even of the same make and model, will vary in actual loaded axle weights, because of different options and personal loads.
While your actual, loaded axle weight should be below the GAWR, you must weigh your motorhome in a loaded condition to know its actual weight. Weigh the front axle, the total unit, and then the rear axle. It is possible for a vehicle to be within the GVWR yet overloaded on an axle. It is even possible for one wheel position to be overloaded, even though the GAWR has not been exceeded. For this reason (if there is room to the sides of the scale) Michelin recommends weighing each wheel position of the vehicle. This will give you a clear indication of exactly how the weight of your motorhome is distributed. The Tire Industry Safety Council publishes a "Recreational Vehicle Tire Care and Safety Guide" which includes instructions on how to weigh your vehicle by wheel position.
Links to selected instructions and diagrams are presented here: Weighing Your Single Axle Recreational Vehicle or Weighing Your Tandem Axle Recreational Vehicle. Print the correct diagram/instruction from the links for your type of RV and use in conjunction with the "How to Weigh Your RV" section found below.
Where to Weigh Your Vehicle
There are probably several certified public scales in your area. You will find public-access scales in a variety of places, such as moving and storage company lots, farm suppliers with grain elevators, gravel pits, recycling companies, and large commercial truck stops.
If you are not aware of a nearby public scale, check your phone book's yellow pages under "scales-public" section or "weighers". A nominal fee will be charged, but this is money wisely spent.
How to Weigh Your RV
Your RV must be weighed fully loaded, that is, with passengers, food, clothing, fuel, water, propane, supplies, etc. Any towed vehicle (car/pickup, boat or trailer) or item loaded on brackets on the back of the RV, such as bikes or motorcycles, should also be included in the weighing.
There are three types of scales: 1. Platform. 2. Segmented Platform. 3. Single Axle.
1. The platform scale is long enough to weight the complete vehicle.
2. The segmented platform scales can provide individual axle weights and total vehicle weights simultaneously, when the vehicle is positioned properly.
3. Single axle scales weigh one axle at a time.
1) The platform scale is long enough to weight the complete vehicle. The following steps are suggested and are illustrated with diagrams found in the above links under "How to Determine Your RV's Correct Weight".
a) Pull onto the scale so that only the front axle is on the platform (with the end of the scale midway between the front and rear axles), and record the scaled weight.
b) Pull forward until the full unit is on the scale, and record the scaled weight.
c) Pull forward so that only the rear axle is on the scale (again with the edge of the scale midway between the front and rear axles), and record the scaled weight.
d) If the RV has a rear tag axle, pull forward so that only the tag axle remains on the scale, and record the scaled weight.
If there is no towed vehicle, this weight will represent the actual weight on the tag axle. To determine the actual load on the rear axle, subtract this value from the recorded weight in step 1c. If there is a towed vehicle, proceed to step 1e (see link above for "Weighing Your Tandem Axle Recreational Vehicle"), to obtain the "towed vehicle only" weight. Subtract that value from the value above and then subtract that from the weight recorded in step 1c.
If a boat, trailer or other vehicle is being towed, it should be weighed and combined with the towing vehicle's GVW (Gross Vehicle Weight) to ensure the total weight does not exceed the GCWR (Gross Combined Weight Rating).
2) The segmented platform scales can provide individual axle weights and total vehicle weights simultaneously, when the vehicle is positioned properly.
Position the vehicle on the scales so that each axle is centered as much as possible on separate segments, and record the weight. Reposition the vehicle so that only one side is on the scale, again centered on the segment as much as possible. Subtract the weighed wheel positions from the total axle weights to determine the unweighed wheel positions' weights.
3) The single axle scale weighs one axle at a time.
Drive your front axle onto the scale and stop long enough for the weight to be recorded. Pull vehicle forward until the rear axle is on the scale. To obtain the gross vehicle weight add the two axle loads together. To obtain the individual wheel position weights, repeat this process with only one side of the RV on the scale.
Note: Even though the weight of the total axle may be within the axle's rating, it may be overloaded on one side. This causes one wheel position to be overloaded. Therefore, side-to-side weighing should also be done.
If there is a difference in the weights on one side of the vehicle as compared to weights on the other side, components (tires, wheels, brakes, springs, etc.) on the heavier side could be overloaded, even though the total axle load is within the GAWR. It is important to redistribute the load to avoid component failure, as well as to improve the handling characteristics of the vehicle. With these actual weights, it is now possible to compare them against the GAWR, GVWR and tire capacities. These weights are also what should be used to help determine the proper air pressure for the tires.
If you are towing a vehicle or trailer, you need to know your RV's GCWR (Gross Combined Weight Ratings). This is the total actual loaded weight of your RV (or tow vehicle) plus total actual loaded weight of the towed vehicle (or trailer). The total actual loaded weight of the RV and towed vehicle should not exceed the GCWR. While the GCWR has more to do with the drivetrain (engine, transmission, axle, brakes, and bearings) design limits, this additional weight can also affect the tires and how your RV (or tow vehicle) handles. And finally, please don't forget to consider the tongue weight of the trailer.
Common Tire Damages and Tire Wear
No tire, regarless of its quality, is indestructible. Certain conditions of use and abuse can stress a tire beyond reasonable operating limits, causing it to come out of service even when considerable tread reamins. Such conditions are clearly indicated by the damage they leave on the tire itself. Below are listed common damages and the signs they leave behind. Please understand that this list is by no means exhaustive and is intended only as a general guide.
Fatigue Rupture
This type of damage is sometimes called a "zipper rip" because of the zipper-like effect it creates in the steel casing cords of the damaged tire. Overload and/or underinflation for a given load, and improper blocking of the tires can cause the steel casing to fatigue and result in this type of damage. As one cord breaks, each cord around it is subjected to even more stress. Eventually the weakened cords may break, one after the other, until a rupture occurs in the upper sidewall.
Dual Kissing
This type of damage refers to what happens when two tires in dual configuraton make contact while in operation. The heat generated by the friction between the two tires severely weakens the casing material of the dual ties. This is easily seen on the sidewalls of the tires where the duals come in contact. The condition may be caused by several factors:
Underinflation
This condition is often referred as a "run flat" tire. It is caused by operating a tire at very low or zero air pressure. When a tire is run at normal highway speeds, underinflated, it flexes too much and builds up heat. This heat damages the inner liner, casing and outer sidewall of the tire. If not remedied quickly, the tire will be irreparably damaged.
In extreme cases, the sidewall of the tire is destroyed, from the excessive heat it endured, due to the weight of the vehicle pressing on the tire casing without the cushioning effect of the correct air pressure, and due to the crushing/cutting action of the wheel as it rolls on the uninflated sidewall. According to guidelines put out by the Rubber Manufacturers Association, any tire that has been run at less than 80% of recommended air pressure for the load it is carrying should be inspected for possible damage.
When one tire in a dual configuration comes out of service due to underinflation/run flat damage, the other tire in the dual configuration should be inspected immediately. If the unserviceable tire was underinflated, that means the serviceable tire was carrying more and more of the load for that wheel position. Consequently, it too may have suffered some casing damage.
Tire Wear
All tires mounted on RV's should wear in a smooth, even wear pattern when the tires are maintained with the correct air pressure for the load on the tire. If tires begin to show an irregular wear pattern, and the vehicle alignment is correct, sometimes just rotating the tires by changing direction of rotation and wheel position will allow the tires to wear evenly.
Toe Wear
A feathered wear pattern on the front tires typically indicates misalignment (toe in or out). Sometimes a radial tire will not have this wear pattern unless the toe condition is severe. Instead of the feathered edge wear, the tire will be worn on the inside or outside shoulder which could be confused with camber wear. A skewed rear axle could show feathered edge wear on one shoulder of one front tire and feathered edge on the opposite shoulder of the other front tire. In order to correctly diagnose a tire wear condition, the motorhome should have the alignment checked on all four wheel positions before any corrections to alignment are made.
Camber Wear
Also known as edge wear, camber wear shows up on the inside or outside shoulders of the tread. Wear on the inside edge of both tires may be due to negative camber or toe-out, a misalignment. If only one tire shows edge wear, check for worn kingpin bushings, bent or worn steering components, or excessive positive camber setting.
Rotation/Cleaning/Tire Life
Tire Rotation
If correct air pressure and proper alignment are both continually maintained, tire rotation may never be needed. However, in other cases, tire rotations may be needed to help even out alignment, underinflation, or free rolling wear problems. Follow your motorhome manufacturer's rotations service recommendations.
Proper Cleaning
Road oil will cause deterioration of the rubber and dirt buildup will help hold the chemicals in the air next to the tire and will also deteriorate the tire.
As with the cleaning of any rubber product, proper care and methods in cleaning must be used to obtain the maximum service yeras out of your tires. A soft brush and the normal mild soap that you would use to clean your RV may be used. If you use a dressing product to "protect" your tires from aging, use extra care and caution. Tire dressings that contain petroleum products or alcohol may cause deterioration or cracking.
In many cases, it is not the dressing itself that can be a problem, but more the chemical reaction that the product can have with the antioxidant compound in the tire. Heat can add to the negative reaction. When these same dressing products are used on a passenger car tire that is replaced every three to four years, it is rare to see a major problem. However, in most cases, RV tires may last much longer due to limited annual mileage, and the chemical reactions have much longer to take effect.
Tire Life
The life of a tire used on an RV cannot be measured by miles alone. Your RV tire life depends on driving habits, driving conditions, and geography, as well as the age of your tires.
Just like your fan belt and radiator hoses, the rubber in your tires ages as well. In cooler, clean air locations, the expected tire life will be longer than in high temperature, high ozone areas. Of course, as a tire ages, you should inspect it more frequently.
Tire Inspection
Your RV tires should be inspected thoroughly at least once a year, and any time you drive in rough or rocky terrain, or when you have your RV serviced.
This inspection should include both the outside and insdie sidewalls, the tread area, and the valves, caps, and any valve extensions. Inspect for nails, cuts, bulges, aging, or fatique cracks and weathering or ozone cracking. Also, check between the duals for objects lodged between them.
During the yearly or pre-trip inspection the tires should be inspected for signs of aging, eather checking and/or ozone cracking. Look for tiny cracks in the rubber surface on the sidwall of the tires. Most often the cracks are 360 degrees around the tire.
If the cracks are less than 1/32" deep, the tires is O.K. to run. Between 1/32" and 2/32", the tire is suspect and should be examined by your tire dealer. If the cracks are over 2/32", the tire should be replaced immediately.
To protect your tires frome these common damage conditions:
Long-Term Storage/Selecting Replacement Tires
Your RV is designed for recreation, not long-term storage. However, unless you are a "full timer", you have no other choice. Rubber tires age faster when not being used. A cool, dry, sealed garage is your best bet for storage. However, many RVs are stored outside in the elements. Some storage surfaces may cause tires to age prematurely. For this reason, Michelin recommends placing a barrier (i.e. card board, plastic, or plywood) between the tire and the storage floor/ground surface.
There are a few steps that you can take to reduce the aging effects from long-term RV storage. Before putting your RV into storage or a non-use period, thoroughly clean your tires. Then cover the tires to block direct sunlight and ultraviolet rays. Store your RV out of a high ozone area. NOTE: When vehicle is stored, tires should be inflated to maximum inflation pressure as indicated on the sidewall of the tire.
Before removing your vehicle from long-term storage, thoroughly inspect each of its tires. This means a close examination of each tire's tread area, and air pressure. If your pressure check indicates the tires have lost air during storage, be sure to inflate them to the correct pressure for the current load before putting the unit into service.
The Use of Blocks to Level Motor Homes/RV's Equipped with Radial Tires
Extreme caution must e taken to ensure that the tires are fully supported when using blocks to level motor homes and/or RV's. The load on the tires should evenly distributed on the block and in the case of duals, evenly distributed on blocks for both tires. If not properly done, the steel cables in the sidewall of the tires may be damaged and could lead to premature fatigue of the sidewall.
The correct and incorrect methods are shown here. Please note that blocks should be wider than the tread and longer than the tire's footprint. This provides maximum support to the tires and assures that the load is evenly distributed throughout the tire's footprint area.
Selecting Replacement Tires for Your RV
One of the most important RV equipment purchases that you will make will be the replacement tires on your RV. If you obrained good service with your first set of tires, chances are that they were matched well for your RV's weight needs and your type and area of driving. You will be sure only if you have weighed your loaded RV.
If there is reason to replace your tires with another size, be very careful with this selection. There are some basic areas of concern, such as the load rating of the new tire and the overall diameter of the new tire for vehicle clearance and speedometer reading.
Then there is the matching of the tires to the dual wheel offset for the dual spacing clearance and the load rating of the wheel. For example: buying a tire with a higher load rating that might equire 105 P.S.I. would be of no advantage if your wheel is limited to 80 P.S.I. (And be sure that the wheel width is compatible with the new tire size). Consult your vehicle manufacturer for wheel specifications.
brought to you by Michelin North America
For more information on the Michelin dealer nearest you, check your local telephone directory or call 1-800-847-3435.
The most important factor in maximizing the life of your tires is maintaining proper inflation. Driving on any tire that does not have the correct inflation pressure for the load of the vehicle is dangerous and may cause premature wear, tire damage, and/or loss of control of the vehicle.
A tire that is underinflated will build up excessive heat that may go beyond the prescribed limits of endurance of the rubber and the radial cords. This could result in sudden tire failure. A tire that is underinflated will also cause poor vehicle handling, rapid and/or irregular tire wear, and a decrease in its fuel economy.
Overinflation will reduce the tire's footprint or contact patch with the road, thus reducing the traction, braking capacity, and handling of the vehicle. A tire that is overinflated for the load that it is carrying will also contribute to a harsh ride, uneven tire wear, and will be susceptible to impact damage.
Maintaining correct tire inflation pressure for each loaded wheel position on your vehicle is of the utmost importance and must be a part of regular vehicle maintenance.
How Much Air Should I Carry in My Tires?
Federal law requires that the tire's maximum load rating be molded into the sidewall of the tire. On the tire's sidewall you can see the maximum load allowed for the size tire and load rating, and the minimum cold air inflation pressure needed to carry that stated maximum load. Utilizing less air pressure means a lesser load can be carried by the tire.
The amount of air pressure you need to use is dependent on the weight of your fully loaded vehicle.
It is important to note that the cold inflation pressure for the tire must never exceed the maximum inflation rating stamped on the wheel.
When Should I Check my RV's Tires' Air Pressure?
You should check the air pressure every two weeks or at least one a month and before any major trip. Your RV tires' air pressure should be checked every "drive" morning on long trips. On short trips of a day or less driving each way, your tires should be checked before you leave on your trip and again before you start your trip home. If your vehicle is stored for any length of time, air pressure should be checked prior to storage, but more importantly, when it comes out of storage.
Check your tires when they are "cold" and have not been driven for more than one mile. The stated load capacity for a given cold inflation pressure is based on ambient outside temperature. If you must check your tires when they are warm or hot, do allow for a slight increase in air pressure and make sure they are within a couple of pounds of each other on the same axle. Never let air out of a hot tire.
It is recommended you purchase a quality truck tire air gauge which has an angled dual head. This type of gauge allows you to check inflations on the inner dual wheel which has the valve stem pointing toward you, and on the outer wheel which has the valve stem pointing away from you. Nothing should restrict your ability to check a tire's air pressure daily when you are driving your RV. Pressure sealing valve caps should always be used to prevent air from escaping from the valve stem. If you use valve stem extension hoses, make sure they are good quality stainless steel braid reinforced and are securely anchored to the outer wheel. If your RV has wheel covers which must be removed to check the inflation, then consider removing them on a long trip, as the extra time and effort required may lead you to avoid checking your air pressure.
What if You Don't Check Your Air Pressure?
If a tire picks up a nail or screw that creates a slow leak and causes some air pressure loss, you might eventually spot it visually if it's a front tire. If it is an outside rear dual, you might also spot it with a visual inspection. However, if it is an inside rear dual, the chances of spotting it without an air pressure check are very slim. If you begin driving without finding it, very quickly (in most cases a few miles) your outside rear tire next to the low air pressure tire is going to heat up from carrying double its load, which will cause both tires to fail. Then you'll have two tires down on the same side and on the same axle, and a five ton or more vehicle at any speed is difficult to bring under control.
How to Determine Your RV's Correct Weight
The GVWR (Gross Vehicle Weight Rating) and GAWR (Gross Axle Weight Rating) stickers on your motorhome (normally located on the support pillar next to the driver's seat) will show you the chassis manufacturer's and/or the motorhome manufacturer's total vehicle maximum weight ratings and per axle weight rating.
The GVWR is the maximum total weight for which the vehicle is rated - including passengers, fluids, and cargo. The GAWR is the maximum for which a single axle is designed. These per axle and total maximum weight ratings could be limited by the tires, wheels, axle and axle bearings, springs, the vehicle frame, or other components of the vehicle.
The GAWR sticker is only a guide in knowing your maximum loaded axle weights and subsequently your correct tire inflation pressure. Every motorhome, even of the same make and model, will vary in actual loaded axle weights, because of different options and personal loads.
While your actual, loaded axle weight should be below the GAWR, you must weigh your motorhome in a loaded condition to know its actual weight. Weigh the front axle, the total unit, and then the rear axle. It is possible for a vehicle to be within the GVWR yet overloaded on an axle. It is even possible for one wheel position to be overloaded, even though the GAWR has not been exceeded. For this reason (if there is room to the sides of the scale) Michelin recommends weighing each wheel position of the vehicle. This will give you a clear indication of exactly how the weight of your motorhome is distributed. The Tire Industry Safety Council publishes a "Recreational Vehicle Tire Care and Safety Guide" which includes instructions on how to weigh your vehicle by wheel position.
Links to selected instructions and diagrams are presented here: Weighing Your Single Axle Recreational Vehicle or Weighing Your Tandem Axle Recreational Vehicle. Print the correct diagram/instruction from the links for your type of RV and use in conjunction with the "How to Weigh Your RV" section found below.
Where to Weigh Your Vehicle
There are probably several certified public scales in your area. You will find public-access scales in a variety of places, such as moving and storage company lots, farm suppliers with grain elevators, gravel pits, recycling companies, and large commercial truck stops.
If you are not aware of a nearby public scale, check your phone book's yellow pages under "scales-public" section or "weighers". A nominal fee will be charged, but this is money wisely spent.
How to Weigh Your RV
Your RV must be weighed fully loaded, that is, with passengers, food, clothing, fuel, water, propane, supplies, etc. Any towed vehicle (car/pickup, boat or trailer) or item loaded on brackets on the back of the RV, such as bikes or motorcycles, should also be included in the weighing.
There are three types of scales: 1. Platform. 2. Segmented Platform. 3. Single Axle.
1. The platform scale is long enough to weight the complete vehicle.
2. The segmented platform scales can provide individual axle weights and total vehicle weights simultaneously, when the vehicle is positioned properly.
3. Single axle scales weigh one axle at a time.
1) The platform scale is long enough to weight the complete vehicle. The following steps are suggested and are illustrated with diagrams found in the above links under "How to Determine Your RV's Correct Weight".
a) Pull onto the scale so that only the front axle is on the platform (with the end of the scale midway between the front and rear axles), and record the scaled weight.
b) Pull forward until the full unit is on the scale, and record the scaled weight.
c) Pull forward so that only the rear axle is on the scale (again with the edge of the scale midway between the front and rear axles), and record the scaled weight.
d) If the RV has a rear tag axle, pull forward so that only the tag axle remains on the scale, and record the scaled weight.
If there is no towed vehicle, this weight will represent the actual weight on the tag axle. To determine the actual load on the rear axle, subtract this value from the recorded weight in step 1c. If there is a towed vehicle, proceed to step 1e (see link above for "Weighing Your Tandem Axle Recreational Vehicle"), to obtain the "towed vehicle only" weight. Subtract that value from the value above and then subtract that from the weight recorded in step 1c.
If a boat, trailer or other vehicle is being towed, it should be weighed and combined with the towing vehicle's GVW (Gross Vehicle Weight) to ensure the total weight does not exceed the GCWR (Gross Combined Weight Rating).
2) The segmented platform scales can provide individual axle weights and total vehicle weights simultaneously, when the vehicle is positioned properly.
Position the vehicle on the scales so that each axle is centered as much as possible on separate segments, and record the weight. Reposition the vehicle so that only one side is on the scale, again centered on the segment as much as possible. Subtract the weighed wheel positions from the total axle weights to determine the unweighed wheel positions' weights.
3) The single axle scale weighs one axle at a time.
Drive your front axle onto the scale and stop long enough for the weight to be recorded. Pull vehicle forward until the rear axle is on the scale. To obtain the gross vehicle weight add the two axle loads together. To obtain the individual wheel position weights, repeat this process with only one side of the RV on the scale.
Note: Even though the weight of the total axle may be within the axle's rating, it may be overloaded on one side. This causes one wheel position to be overloaded. Therefore, side-to-side weighing should also be done.
- To determine individual wheel position weights, it is necessary to repeat the previous three steps (1a, 1b and 1c), but this time, use only one side of the scale, as shown in the diagrams (see links above)
- To calculate the opposite side of the vehicle wheel position weight, subtract this side's weight from the weights recorded in steps 1a, 1b and 1c.
If there is a difference in the weights on one side of the vehicle as compared to weights on the other side, components (tires, wheels, brakes, springs, etc.) on the heavier side could be overloaded, even though the total axle load is within the GAWR. It is important to redistribute the load to avoid component failure, as well as to improve the handling characteristics of the vehicle. With these actual weights, it is now possible to compare them against the GAWR, GVWR and tire capacities. These weights are also what should be used to help determine the proper air pressure for the tires.
If you are towing a vehicle or trailer, you need to know your RV's GCWR (Gross Combined Weight Ratings). This is the total actual loaded weight of your RV (or tow vehicle) plus total actual loaded weight of the towed vehicle (or trailer). The total actual loaded weight of the RV and towed vehicle should not exceed the GCWR. While the GCWR has more to do with the drivetrain (engine, transmission, axle, brakes, and bearings) design limits, this additional weight can also affect the tires and how your RV (or tow vehicle) handles. And finally, please don't forget to consider the tongue weight of the trailer.
Common Tire Damages and Tire Wear
No tire, regarless of its quality, is indestructible. Certain conditions of use and abuse can stress a tire beyond reasonable operating limits, causing it to come out of service even when considerable tread reamins. Such conditions are clearly indicated by the damage they leave on the tire itself. Below are listed common damages and the signs they leave behind. Please understand that this list is by no means exhaustive and is intended only as a general guide.
Fatigue Rupture
This type of damage is sometimes called a "zipper rip" because of the zipper-like effect it creates in the steel casing cords of the damaged tire. Overload and/or underinflation for a given load, and improper blocking of the tires can cause the steel casing to fatigue and result in this type of damage. As one cord breaks, each cord around it is subjected to even more stress. Eventually the weakened cords may break, one after the other, until a rupture occurs in the upper sidewall.
Dual Kissing
This type of damage refers to what happens when two tires in dual configuraton make contact while in operation. The heat generated by the friction between the two tires severely weakens the casing material of the dual ties. This is easily seen on the sidewalls of the tires where the duals come in contact. The condition may be caused by several factors:
- improper mounting
- incorrect dual spacing
- underinflation
- "casing growth"
Underinflation
This condition is often referred as a "run flat" tire. It is caused by operating a tire at very low or zero air pressure. When a tire is run at normal highway speeds, underinflated, it flexes too much and builds up heat. This heat damages the inner liner, casing and outer sidewall of the tire. If not remedied quickly, the tire will be irreparably damaged.
In extreme cases, the sidewall of the tire is destroyed, from the excessive heat it endured, due to the weight of the vehicle pressing on the tire casing without the cushioning effect of the correct air pressure, and due to the crushing/cutting action of the wheel as it rolls on the uninflated sidewall. According to guidelines put out by the Rubber Manufacturers Association, any tire that has been run at less than 80% of recommended air pressure for the load it is carrying should be inspected for possible damage.
When one tire in a dual configuration comes out of service due to underinflation/run flat damage, the other tire in the dual configuration should be inspected immediately. If the unserviceable tire was underinflated, that means the serviceable tire was carrying more and more of the load for that wheel position. Consequently, it too may have suffered some casing damage.
Tire Wear
All tires mounted on RV's should wear in a smooth, even wear pattern when the tires are maintained with the correct air pressure for the load on the tire. If tires begin to show an irregular wear pattern, and the vehicle alignment is correct, sometimes just rotating the tires by changing direction of rotation and wheel position will allow the tires to wear evenly.
Toe Wear
A feathered wear pattern on the front tires typically indicates misalignment (toe in or out). Sometimes a radial tire will not have this wear pattern unless the toe condition is severe. Instead of the feathered edge wear, the tire will be worn on the inside or outside shoulder which could be confused with camber wear. A skewed rear axle could show feathered edge wear on one shoulder of one front tire and feathered edge on the opposite shoulder of the other front tire. In order to correctly diagnose a tire wear condition, the motorhome should have the alignment checked on all four wheel positions before any corrections to alignment are made.
Camber Wear
Also known as edge wear, camber wear shows up on the inside or outside shoulders of the tread. Wear on the inside edge of both tires may be due to negative camber or toe-out, a misalignment. If only one tire shows edge wear, check for worn kingpin bushings, bent or worn steering components, or excessive positive camber setting.
Rotation/Cleaning/Tire Life
Tire Rotation
If correct air pressure and proper alignment are both continually maintained, tire rotation may never be needed. However, in other cases, tire rotations may be needed to help even out alignment, underinflation, or free rolling wear problems. Follow your motorhome manufacturer's rotations service recommendations.
Proper Cleaning
Road oil will cause deterioration of the rubber and dirt buildup will help hold the chemicals in the air next to the tire and will also deteriorate the tire.
As with the cleaning of any rubber product, proper care and methods in cleaning must be used to obtain the maximum service yeras out of your tires. A soft brush and the normal mild soap that you would use to clean your RV may be used. If you use a dressing product to "protect" your tires from aging, use extra care and caution. Tire dressings that contain petroleum products or alcohol may cause deterioration or cracking.
In many cases, it is not the dressing itself that can be a problem, but more the chemical reaction that the product can have with the antioxidant compound in the tire. Heat can add to the negative reaction. When these same dressing products are used on a passenger car tire that is replaced every three to four years, it is rare to see a major problem. However, in most cases, RV tires may last much longer due to limited annual mileage, and the chemical reactions have much longer to take effect.
Tire Life
The life of a tire used on an RV cannot be measured by miles alone. Your RV tire life depends on driving habits, driving conditions, and geography, as well as the age of your tires.
Just like your fan belt and radiator hoses, the rubber in your tires ages as well. In cooler, clean air locations, the expected tire life will be longer than in high temperature, high ozone areas. Of course, as a tire ages, you should inspect it more frequently.
Tire Inspection
Your RV tires should be inspected thoroughly at least once a year, and any time you drive in rough or rocky terrain, or when you have your RV serviced.
This inspection should include both the outside and insdie sidewalls, the tread area, and the valves, caps, and any valve extensions. Inspect for nails, cuts, bulges, aging, or fatique cracks and weathering or ozone cracking. Also, check between the duals for objects lodged between them.
During the yearly or pre-trip inspection the tires should be inspected for signs of aging, eather checking and/or ozone cracking. Look for tiny cracks in the rubber surface on the sidwall of the tires. Most often the cracks are 360 degrees around the tire.
If the cracks are less than 1/32" deep, the tires is O.K. to run. Between 1/32" and 2/32", the tire is suspect and should be examined by your tire dealer. If the cracks are over 2/32", the tire should be replaced immediately.
To protect your tires frome these common damage conditions:
- Keep tires properly inflated
- Keep tires clean
- Avoid prolonged exposure to heat, cold or moisture
- Cover your tires when vehicle is not in use
- Do not park near electric generators or transformers
- Do not store vehicles in an area where welding is being done or in a garage which has mercury vapor lamps
Long-Term Storage/Selecting Replacement Tires
Your RV is designed for recreation, not long-term storage. However, unless you are a "full timer", you have no other choice. Rubber tires age faster when not being used. A cool, dry, sealed garage is your best bet for storage. However, many RVs are stored outside in the elements. Some storage surfaces may cause tires to age prematurely. For this reason, Michelin recommends placing a barrier (i.e. card board, plastic, or plywood) between the tire and the storage floor/ground surface.
There are a few steps that you can take to reduce the aging effects from long-term RV storage. Before putting your RV into storage or a non-use period, thoroughly clean your tires. Then cover the tires to block direct sunlight and ultraviolet rays. Store your RV out of a high ozone area. NOTE: When vehicle is stored, tires should be inflated to maximum inflation pressure as indicated on the sidewall of the tire.
Before removing your vehicle from long-term storage, thoroughly inspect each of its tires. This means a close examination of each tire's tread area, and air pressure. If your pressure check indicates the tires have lost air during storage, be sure to inflate them to the correct pressure for the current load before putting the unit into service.
The Use of Blocks to Level Motor Homes/RV's Equipped with Radial Tires
Extreme caution must e taken to ensure that the tires are fully supported when using blocks to level motor homes and/or RV's. The load on the tires should evenly distributed on the block and in the case of duals, evenly distributed on blocks for both tires. If not properly done, the steel cables in the sidewall of the tires may be damaged and could lead to premature fatigue of the sidewall.
The correct and incorrect methods are shown here. Please note that blocks should be wider than the tread and longer than the tire's footprint. This provides maximum support to the tires and assures that the load is evenly distributed throughout the tire's footprint area.
Selecting Replacement Tires for Your RV
One of the most important RV equipment purchases that you will make will be the replacement tires on your RV. If you obrained good service with your first set of tires, chances are that they were matched well for your RV's weight needs and your type and area of driving. You will be sure only if you have weighed your loaded RV.
If there is reason to replace your tires with another size, be very careful with this selection. There are some basic areas of concern, such as the load rating of the new tire and the overall diameter of the new tire for vehicle clearance and speedometer reading.
Then there is the matching of the tires to the dual wheel offset for the dual spacing clearance and the load rating of the wheel. For example: buying a tire with a higher load rating that might equire 105 P.S.I. would be of no advantage if your wheel is limited to 80 P.S.I. (And be sure that the wheel width is compatible with the new tire size). Consult your vehicle manufacturer for wheel specifications.
brought to you by Michelin North America
Proper septic tank maintenance
Proper septic tank maintenance
As an RV technician I have worked on my share of plugged tanks and valves that stick. Septic tanks are the most hated job in my line of work for good reason. Many of the problems are preventable with good maintenance.
Always start your trip by perching your tank with a few gallons of fresh water, the proper amount of tank sanitizer and a little gate valve lubricant. As you drive to you destination the fresh water mix will slosh inside of the tank. The mix will clean the sides of the tanks, lube the valves, and keep probes clear of debris.
When arriving at your destination you will stretch a hose to the sewer hole. If you are staying for a while you will want to have a hose support that causes a slight down hill run from the RV to the sewer hole. The black tank valve will remain shut while using the RV. You want the liquids to build up to help flush the solids out of the tank when the time comes to dump the tanks. Flush the tank after dumping by closing the black tank valve and running water into the tank. It is very important to stay with the hose as you flush the tank. Getting distracted while flushing can be a disaster if you flood the coach. The gray water tank valve can be left open if you prefer. In my opinion, I would leave the gray valve closed and use the gray to help flush the black water out of the hose.
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