Hi everyone. My 91S2 have a vibration in the steering starting at 70km and over, though I have replaced tires, balanced and aligned front end. On a perfectly smooth road the vibration disappears. As soon as the car gets on just a little uneven surface the vibration comes back.
Please, help.
Thanks, Alex

 

Hi
If the wheels/tires are balanced and its OK on a good road surface, you need to first I would suggest to check steering geometry ie toe in. If that is OK then you need to be looking for a little play in the steering linkage, ie track rod ends, ball joints at the end of the steering rack, play between rack and pinion, excess front wheel bearing play.
Start there and let us know what you find.
Regards Big Bob

 

Thanks Bob. I have spoke to the mechanic who did a wheel alignment and he says he inspected all those things you have mentioned, because he would not start to do any alignment work without thoroughly checking all suspension. He suggested to bring it back to the shop, very expensive porsche shop, to check and possibly to replace struts (another expensive proposition). What do you think?

 

Hi
It is always easy to advise other people to spend their money. Clearly the mechanic is not absolutely certain that it is the struts either, buthe might be right!
How much will itcost if he's right?
The other thought is: as there is clearly nothing that is obviously wrong with your suspension, or dangerous or the mechanic would have said, is the vibration so bad that you cannot live with it?
If you cant live with it ,then you want some guarantee from the OPC that this is the cause and spending the money will solve the problem.
If you can live with it, wait a bit and save the money for now.
Best advice I can give.
Sometimes the hardest thing to do is tohave a problem and not to try to fix it! Thats why my wife hates me finding any noise or vibration on my cars.
Regards Big Bob

 

Did you check your wheel bearings? My car has steering vibration at about 55 mph. Steer tire tread is wearing uneven and my wheels have slight play when twisting them.

 

Speeddreemin is right wheel bearings can play a part, but so do all the other items in an earlier post.
Regards Big Bob

 

You'd probably here noises from the bearings. Good chance it may be the struts if you've already checked all the other things BB mentioned.

 

Could be any of those things. I'm sure Doc would know.