With the advent of basement motorhomes, higher centers of gravity, and softer springing, many drivers have been bothered by road wander. As steering components wear and rear springs have been reduced from 10-12 leaf springs per side to four, the rear of the motorhome sometimes wags the dog during lane change manoeuvers.

At the Louisville RV Show this year, I was introduced to Rob Henderson and his brother John by an old friend, Frank Hone. For several months, Frank had been extolling the virtues of the SuperSteer bell cranks for owners of the P32 GM motorhome chassis, and the SuperSteer rear stabilizing bar for newer motorhomes.

Rob and John took over a business created by their father who started the operation in 1961. Rob's interest in stock car racing pointed out the necessity of good handling characteristics for vehicles, especially long Class A motorhomes. The experience of driving a Class A motorhome in heavy gusty winds, winding roads, and with passing trucks can leave many drivers with white knuckle syndrome as they constantly correct the steering to keep their vehicle headed straight down the road.

The bell crank is fastened securely to the chassis to provide a pivot point for the steering control rods through ball joints and drag links. We have all heard of motorhomes that develop a shimmy at certain speeds where the driver has to slow down to prevent the front wheels from wiggling side to side. This is often caused by looseness in the steering train components or loose wheel bearings. The original bell cranks installed by General Motors had a simple babbitt type bearing surface that could wear quickly and need adjustment or rebuilding within a few thousand miles. This affects the looseness of the steering causing the motorhome to wander, and the wheels to go out of alignment.

Before any work is done on a motorhome to correct road wander, it must be road tested with actual weights recorded as the vehicle would normally be driven. The vehicle is weighed at each wheel, the coupling between the steering column and the gear box is checked, all suspension components are checked for play including the bell crank arms, the steering damper, and the wheel bearings. The ride height of the front suspension is checked and anti-sway bar bushings are checked for wear.

The bell cranks designed by Henderson Lineup use tapered roller bearings instead of the original in-line bearings that can bell-mouth from steering movements that exert tremendous pressure on the shaft. The new bell cranks are greased and sealed for life, then guaranteed for thousands upon thousands of miles. (Top)

Often the original 1 1/4" front stabilizer bar must be changed to a larger diameter such as the 1 5/8" one supplied by iPD with urethane bushings to prevent the front of the motorhome from diving in turns and sudden stops. Many owners of motorhomes don't forget to fill up with fuel before each trip, but seldom think about whether the wheel bearings are properly greased or adjusted correctly.

Shock absorbers do wear out after many trips and the Henderson Lineup shop uses Bilstein/Koni shocks to replace the original equipment. The purpose of the shock absorbers is to keep the tires in constant contact with the road, and to prevent porpoising after going over a bump. As the tires bounce up and down on rough roads the tread often becomes scalloped.

The original equipment hydraulic steering damper installed on the chassis at the factory is not sufficient to keep the steering straight ahead when the tires strike potholes or large bumps.(often called bump steer). Especially when a front tire blows out after the casing has been damaged by a pothole. I always recommend changing the stabilizer to a heavy-duty model such as the Safe-T-Plus supplied by Henderson Lineup. This will add more steering control, comfort and safety when encountering ruts, wind, passing trucks, and blowouts. (We had a front left tire blow out a few minutes after striking a piece of lumber lying on the roadway and were able to come to a safe straight-line stop at the right edge of the road.) It is difficult to dodge an alligator (debris left on the road) that you can't see until after the vehicle in front of you has swerved to pass it.

The GM chassis has air bags inserted in the middle of the coil springs to beef up the carrying capacity of the front-end suspension. These air bags should be inflated to a minimum of 30 PSI and a maximum of 100 depending on the air bag. If the bags are not checked once in a while, they can loose their air pressure and get pinched by the coil springs. Don't check them every day as they can lose three pounds pressure each time you connect your air gauge. We carry 40 PSI in the air bags on our personal motorhome. The ride height affects the front-end alignment. Henderson supplies replacement suspension springs for the GM motorhome chassis in four strengths depending on the actual weight of the vehicle including the driver and passenger.

After 1993 GM changed the leaf spring arrangement from 10-12 leaf springs on each side to the new four leaf parabolic taper leaf spring in the rear to give a softer ride. This change by the manufacturer produced rear axle side-to-side shift that is often the cause of rear end sway, and delayed steering response. The SuperSteer Rear Stabilizer Bar bolts to the frame on one side and to the axle on the opposite side to eliminate driver fatigue from constant corrections needed to correct the tail wagging the dog. This also helped minimize body roll and sway, and allows the axle to move up and down as road conditions demand for a smoother ride. The Stabilizer Bar is a pan-hard rod with threaded ends to allow adjustment of its length to suit the chassis configuration. The urethane bushings at each end are lubricated on installation and do not require any more lubrication for about 50,000 miles. No drilling is required as the frame bracket clamps to the chassis, and the axle bracket is attached with ÒUÓ-bolts. The Stabilizer Bar is also very effective in preventing rear end sway on motorhomes on Ford V10 and F53 chassis and units with air bag or MorRyde rear suspensions. The Bar prevents the axle from moving side to side under the chassis as the suspension deflects from one side to the other like sitting on a large balloon.

Henderson Line-Up Brake & RV supplies many Canadian dealers with the suspension improvements needed for a motorhome that is more comfortable and safe to drive. To find the name of a dealer near you who can install these components, contact Henderson's at www.hendersonslineup.com or call them at 1(800) 245-8309. (Top)