Contour Enthusiasts Group Archives Forums General Troubleshooting Front End Shimmy

I have a 95 Contour MTX and I have been having an on-going shimmy problem for a long time. Old tires new tires, rims are bang-on. Brakes are new and there is no problem with the bearings. The shimmy is intermittent - could it be a CV joint that is bent? In addition, could it be caused by something turning in the MTX(I'm desperate for a solution)?
Please help,
Thanks,
Rob

First off, are you sure your tires are round? This is not a balancing issue. I tried out some new FS SH-30s and even when balanced I had considerable shimmy from day of install. This went through 3 sets and had no luck. I put car up on jacks, put handbrake on as tight as possible, blocked rear wheels and then started car and put into low. The tires were out of round while wheels were not. When both out of roumnd tires syncronized up at times shimmy was unbelivable for new tires. (I changed to Michelin XGTs after that.)
It is easy to visually spot if tires or wheels are out of round at this point with this method. A 1/4 inch out of round will cause the symptoms.
However keep safety in ind and do not rev engine. Let wheels turn at engine idle speed. let a shop do on a hoist if you are not comfortable with this method.

If is is not wheels or tires suspect a suspension or steering componet. MacPherson strut front suspensions are notorious for shimmy.

Hi,

Thanks for the information. It has been confirmed that the tires are round and in balance. Can you give me a little more information about the McPherson strut issue. What's the problem there? I find that the shimmy is intermittent not only with speed but with times as well that's why I'm leaning towards something more obscure. Any information would be appreciated.
Thanks,

Any slop or wear in suspension or steering components on many MacPherson strut suspensions can cause bad dynamics & harmonics. I had a Mazda R100 (Rotary engine)at slow to medium speeds where front wheels and steering wheel would just start shimmying back and forth in an extreme manner. It would then go away at higher speeds. This is similar to the problem found on some older Ford pickup trucks where at certains speeds the whole front end just starts going bannas and you would swear the truck was going to shake itself to death or even flip over. I have personally seen this happen to a Ford pickup and its actually looks like the wheels have gone square with all the shaking. Just bad suspension dynamics when things get out of spec (even a little bit).
Thus you should have the slack on all steering components checked, replace bushing were required (go to urethane replacements). You may even have to change the steering rack if that is out of spec. Also related, check that alignment is what it is supposed to be first.