Steering Wheel Vibration

[xjaywalker]

Hi All,

New to the forum and a new (actually used) MH. We bought a 06 National Tropi-Cal T396 on the Freightliner XC Chassis.

We took off on our first little trip (300 miles RT) to Borrego Springs and I noticed some vibration between 35-55 MPH during all road conditions but worse on worn older roads with dips and pot holes (a lot of old roads out in the desert). The orignal owner added steering stabilizers, but I have a feeling this maybe balance or alignment issues. ?????? But I know nothing about motorhomes.

Any help is greatly apprieciated.

Xjaywalker

RSM,CA

[wolfe10]

Go to a tire dealer or front end shop that works with OTR trucks/motorhomes.

Look for unusual tire wear-- roate tires to the rear and bring best side's rear tires forward if unusual wear (but tires still servicable).

Have him jack up the front end and:

Check tires for run-out. Even a well balanced egg-shaped tire will...... well, it will roll like an egg.

If more than .035", fix it-- rotate tire on wheel, wheel on hub or have tire trued. If need be, swap better tires from the rear to the front.

Then have the front tires balanced ON THE COACH. You want all the rotating mass in balance, not just the tire and wheel. If that 100 pound brake drum or disk is out even a few ounces, it needs to be accounted for.

If you tell us where you are, perhaps someone can recommend a particular shop.

[hermanmullins]

xjaywalker,

I went to Bear Alignment school too many years ago. One of the things I learned was if you feel a shimmy in the steering wheel the problem is in the front end. Balance, shocks,alignment, ball joints or king pins, tie rod ends or idler arm. However if you feel the shimmy in your seat it is in the rear end. Most of the time the shimmy in the rear is shocks. But it could also be worn out bushings.

If your front tires a cupped it could be balance. How does your coach track down the road. Does it pull in either direction? Does your coach wander from left to right? That could be a sign of toe-in being out. With the toe-in out one wheel will be trying to go streight and the other will being trying to correct it self.

As Brett said an OTR Shop that speiclizes in alignment woud be the right choice to make.

[lk2369]

I had a 2005 Itasca Horizon that had a steering wheel shimmy from the time it was new until 37,000 miles were driven. During that time (four years), I took it to the local Freightliner facility twice and three different truck tire shops. They balanced the wheels, installed Tru-balance wheel centering, installed Equal in the tires, etc. No one could solve the problem so I continued driving with the annoying shimmy, even after installing new Michelin tires.

Later, I called Tolleson Freightliner, west of Phoenix. Kirk Ault, the Service Manager, assured me they could eliminate the shimmy. When we passed through Arizona, I took my coach to them. They measured the radial runout and found it out of spec. They rotated the tires on the rims until the runout was within spec. This solved the problem. When I drove away the steering wheel was perfectly smooth at all speeds for the first time ever.

Note: On several of the many failed attempts to solve the problem, I asked the service person to check the radial runout. Each time they said they did and it was in spec. They either did not know how to properly check the radial runout or they never actually checked it. As I recall, it takes a special tool that some tire shops do not have.

Good luck.

[rhuffhines]

I had all 6 tires trued and rebalanced and it gave me a smooth ride. Hard to find someone that trues tires anymore . Used Hunt Tire Service out of Winchester TN.

[xjaywalker]

Go to a tire dealer or front end shop that works with OTR trucks/motorhomes.

Look for unusual tire wear-- roate tires to the rear and bring best side's rear tires forward if unusual wear (but tires still servicable).

Have him jack up the front end and:

Check tires for run-out. Even a well balanced egg-shaped tire will...... well, it will roll like an egg.

If more than .035", fix it-- rotate tire on wheel, wheel on hub or have tire trued. If need be, swap better tires from the rear to the front.

Then have the front tires balanced ON THE COACH. You want all the rotating mass in balance, not just the tire and wheel. If that 100 pound brake drum or disk is out even a few ounces, it needs to be accounted for.

If you tell us where you are, perhaps someone can recommend a particular shop.

We are in Rancho Santa Margarita, CA however the coach is stored in Corona, CA... Thanks for your help.

[pscarey1]

Pete's Road Service in Fullerton. I have gone there and they were very helpful. http://www.petesrs.com/

[dickandlois]

I copied over some information in regards to the vibration.

The last item is what you described and will not really help, but might be worth making a copy for your records.

****.

Ride Glossary of Terms and Diagnostics

• Bounce - Bouncing may occur in the front of the coach, the rear or both. Drive the coach on a rough or uneven road surface to determine if this condition exists.

• Delayed Steering Response - A slow gear ration will produce a slow steering response. This problem may also be caused by rear axle side-shift. Evidence of delayed steering response may be produces by small steering wheel adjustments at highway speeds.

• Dog Tracking - This is where the rear wheels of the vehicle do not follow or line up with the front wheels. The coach appears to be moving forward in a crooked fashion. Drive on a straight road. Look in the side mirror. The distance between the front wheel and the highway line will be different than the distance between the rear wheel and the highway line.

• Harsh Ride - The vehicle rides stiff. You can feel every crack, rut or bump in the road. This condition should be obvious to all passengers in the coach.

• Noise - Noises can come in many forms: rattles, clunks, tinny sounds, solid noises, etc. Are those noises produced while driving over small bumps or large potholes? Take another person with you and try to duplicate that noise so you can determine where the problem exists and how it may be resolved.

• Noise - Noises can come in many forms: rattles, clunks, tinny sounds, solid noises, etc. Are those noises produced while driving over small bumps or large potholes? Take another person with you and try to duplicate that noise so you can determine where the problem exists and how it may be resolved.

• Porpoising - The coach will teeter-totter in a front to back movement. Go over a freeway overpass where the pavement rises suddenly or over a gradual dip. This test will demonstrate if this condition exists.

• Pull - The coach drifts to the right or left when driving. The driver feels the steering wheel pulling to one side or the other.

• Returnability - As a turn is made, does the vehicle naturally come back to center? As you make a gradual left or right turn and let go of the wheel, if the coach does not come back to center, then there is poor returnability.

• Road Wander - With this condition, the coach "has a mind of its own". It wants to move left or right even if the driver is driving straight. The coach also wants to travel its own way after hitting ruts. Keep the steering wheel straight ahead and see where the coach goes. Hit a rut and determine how the coach reacts.

• Rut Tracking - The coach follows the grooves worn in the road (created often by 18-wheelers) or where ridges are created when an asphalt surface meets a concrete road surface. The coach wants to continue in the direction of the ridge or groove and it is difficult to correct or change the path of the coach. Find a similar road surface indicated above and test the vehicle for this response.

• Steering Play - This indicates the amount of free play in the steering wheel. When a driver moves the steering wheel to the left or right, there is little immediate response. Turn the steering wheel back and forth and determine if little reaction or turning is taking place.

• Sway - The coach leans, sways or rocks in a side to side motion with a distinct feeling of top heaviness. This may be presented when doing quick lane changes, cornering or entering unlevel driveways.

• Tail-Wagging the Dog - This is where the rear end of the coach tends to sway or slip to one side or the other. Making sudden lane changes or windy conditions often produce this problem. Small steering corrections may also produce tail-wagging the dog.

• Vibration - There are two kinds of vibration: steady or pulsating. The key is determining the source of the vibration. Is the vibration or pulsations coming from the steering wheel? Through the floor? Specific to certain speeds? It is like solving a puzzle.