Hi all, I get a vibration, felt mostly in the steering wheel I think, when the car gets up to about 70 mph but it seems to dissipate after about 90 mph. Wheel balancing and alignment have been done. Any thoughts?

 

How many miles on the car? Are the front control arm bushings original?


Andreas

 

About 70,000. I'm pretty sure they are original. How does one test/assess them?

 

I think many will echo my thoughts that original 993 control arms bushings will most certainly be past their prime at this point. For validation, get the front of the car on stands and then use a pry bar between the subframe & the front portion of the arm that houses the bushing.
You should see excessive flex and very obvious cracks in the old rubber.


Andreas

 

Control arm bushings. I’d put money on it.

Get Walrods. Problem solved.

 

+1

 

Also, consider getting the wheels balanced again as the lowest skilled worker in a shop generally does this task and the equipment can also be out of adjustment.
Did you have this problem before the wheel servicing?

 

Yes it was the reason for the balancing.
I was told - re the control arm bushings - that "all components" of the suspension system are "checked" before doing an alignment, so presumably done, but I am taking it back for a re-check.

 

Verdict is in: It is the bushings.
Apparently it's going to take 2-3 weeks for them to arrive from Germany but my guy says that he may be able to fabricate them... Has apparently done so before...

 

If you lived in the US, I could rebuild your control arms, or send a rebuilt set for exchange. I've rebuilt between 80 - 90 sets of 993/964 arms for Rennlisters over the last 10+ years...

But shipping to Canada would probably be prohibitively expensive.






Andreas

 

elephant motorsports sport bushing for the fronts. Done. you want rubber bushings if you are doing anything but hardcore track work.