Shimmys at 75mph, what would it be

[Topless]

Originally Posted by OldMacTech

Hadn't been on the interstate for awhile, this afternoon got it up to speed.
Around 70-75 when the steering wheel started shaking. Every few seconds it would smooth out but if I hit a little bump or accelerated it would wobble again.

Tires?
Wheels?
Ball joints?

Best guess.


Thanks.

Jb

It's always a process of elimination. These questions should narrow the field a bit.
Model, mileage and yr of car?
Tire size, type and age?
Wheel size and Porsche OEM or aftermarket?
Any recent suspension or alignment work done?
Car been sitting for a long time without being driven?

[j.fro]

Got a buddy with another Boxster? Swap front wheels with him. I've got 2 sets of wheels, and when one set (usually the race tires) goes out of balance I get exactly what you describe.
FWIW, get lifetime balancing next time around, and have it done every 6 months.

[OldMacTech]

97 model. 78,000 miles.
Tires are good but not high quality-
1 wheel slightly curbed.
Always had a small shimmy around the same speed but noticeably worse today. ( does not get driven every day)
Was really wondering if since it seems to come and go after bumps if that was any indication of shocks or ball joints or more likely tires/wheels.

Thnx.

Jb

[Topless]

Yes. On a 97 with 78K miles it is tires/wheels/shocks/ball joints/alignment most likely and any of these things could potentially cause shimmy at speed. Swap wheels and it goes away? Tires or wheels are your problem. Doesn't go away? Shocks, alignment or ball joints are your problem.

Simply eliminate the possibilities one by one until your cause presents itself.