drb007

Here's the situation:
I have a 1990 C4 coupe with 102,000 miles. I have a set of 17 inch summer rims that I run Michelin Pilot Sports on, and a set of design 90 16 inch rims with Blizzaks for the winter. Last fall, I noticed that as the Pilots wore, I had a bit of a wobble, like a wheel out of balance. I had the fronts balanced, and it improved.
I put the new Blizzaks on, and shortly therafter I had the wobble again. I finally took it in and had the fronts rebalanced. I am not all that impressed with the shop, and the wobble is still there.
But the more I drive it and really pay attention, it seems like more than a balance issue.
Here are the details I have noticed.
It is often worse when cold...not like a flat spot, but an actual "make the steering wheel shake" wobble.
It does not consistantly happen at a certain speed.
When cruising down the road at 70 mph, it is barely noticable. But if I hit the brakes to slow down, it can be quite bad...not like a warped rotor...and it will keep shaking as I decellerate with the brakes off...
Could this be something with the front suspension, such as a worn set of bushings, wheel bearing, etc, or is a 964 just that sensitive to a really well balanced wheel?
I got the car a year ago, and have not had it aligned. The tires do not wear funny.
Any ideas?

garrett376

I would think that if the car is that sensitive to a well balanced wheel, it has something worn out of tolerance in the suspension - whether it be a wheel bearing, ball joint, or steering arm. Usually you can check things by grabbing them and giving them a shake when the car is on a jack - even grabbing the wheel when it's still on to give you leverage to shake it back and forth. I would vote for something worn out - likely a steering arm bushing, or a-arm ball joint. If it was a wheel bearing I'd think it would occur more readily and in my experience, decrease when the brakes are applied. I'd find a place to check the bushings if you don't do it yourself, and have them check the alignment, too. Keep us posted!

John Boggiano

I used to have something similar happen. It turned out that the wheel was actually slightly distorted side-to-side.

IanR

Also had something like this - turned out to be worn wishbone bushes. There was a slight wobble pretty much all the time, which got much worse under braking.