INSTRUCTOR: Eric Davis

This class might be called: Do you drive it -- or does it drives you?

RV/chassis manufacturers try to accomodate the conflicting needs for maximizing the carrying capacity while still offering a comfortable (not-too-stiff) ride.

STEERING PROBLEMS

Good place to start: Replace 8R-19.5 Michelin (problem w/these) w/2 front 225/70 (19.5") Most steering problems come from the front tires. Handling is also affected by RV weight distribution. It needs to be even. Lots of RVers know the total weight of their units; but few of them know whether the weight is evenly distributed side to side...

Steering and suspension problems fall into several categories:

• Steering wander & drift on perfect road & no wind:
• Rut tracking
• Tail wagging: Weight behind rear axle tends to overpowers the motorhome, and impacts steering. Motorhome unfortunately all too often have no rear sway bar. P/ups same. Buy "Camper Special", as it will add swaybar to rear. P/u swaybar usually only on front -- where most truck weight is:
• Bottoming out: Run out of travel in your suspension -- jarring, mechanical feeling. Similar is spring bind, when springs come in contact w/themselves.
• Porpoising: Weight in rear plus inadequate shocks in front. In extreme conditions the front wheels can come off ground.

Coach construction used to be based on who could build a coach the most inexpensively, and therefore sell it at the lowest price. The last two years has witnessed some dramatic improvements.

P-30 Chevy chassis: Weakest link is front shocks & swaybar. Change the front sway bar and (very importantly) the brackets. This should provide 16 times the previous sway control. On the rear, change the brackets only.

Aligning the front end on motorhomes: First set all tires to maximum pressure; then ensure any airbags are inflated to their normal pressure -- and then do the alignment.

This instructor doesn't like airbag because it tends to be a band-aid solution. He prefers to have proper coil springs, and recommends changing them if necessary.

It's quite surprising to learn how many RVs and tow vehicles have suspension problems they don't even know about. You need to crawl under your coach once a month...check all the brackets. Familiarize yourself with what's there. 5-10% of all units are driving around w/broken brackets, which translates to a completely ineffective swaybar system.

Ford Chassis: Ford has been better than Chevy in addressing suspension and handling.

SHOCK ABSORBERS:

Stock shocks can wear out in 10,000 miles. Real gas shocks have 360 lbs of air pressure. Unfortunately stock vehicles are often not well designed with respect to capacity & the types of shocks used. Bilstein is the top product. Monroe shocks are indicated by this instructor to be inadequate. Some RV mfgrs are now using good quality gas shocks.

There is a very significant difference between fifth wheels which include shock absorbers in the chassis construction, and and those which do not. Shock absorbers protect the suspension system, tires, and the life of vehicle. But original equipment shocks are often good for only about 10,000 miles. The use of shock absorbers by some fifth wheel manufacturers is a good indication of a superior quality fiver.

STEERING STABILIZER: Resisance/return to center pressure. Resists shimmying. SteerSafe and SteerPlus are the two most popular products. They are okay, but often problems are really related to inadequate swaybar, shocks, or springs. Thus stabilizers too are a band-aid approach to steering problems, masking some other more basic problem with the suspension. In order of priority, the most important component is the swaybar; the second most important component is the shock absorber.

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