I've been feeling a lot of vibration on the freeway in my street 914. Had all the tires rebalanced and checked the front wheel bearing tightness. (Did tighten one side down a bit.) No shimmy in the steering wheel now, but still feeling a vibration in the car, so it must be something coming from the back end, but with newly balanced tires, don't know what it might me. I think of rear wheel bearings as whining when they wear out rather than exhibiting any shimmy. Am I wrong on that? Could the rear bearings be worn out? The CV joints look fine on the exterior. Is it possible for a CV joint to get so out of balance than it transmits a shimmy into the car?

Any thoughts or suggestions would be appreciated.

Andrew Blyholder

Check the rear suspension ears and CV joints.

center your wheels on the hubs

Check the bushings on the rear control arms. I had a shimmy that would come and go on the freeway and that was the culprit.

All good suggestions. Thanks, I'll check them all out.

Andrew

If you feel the vibration in the steering wheel, it's most likely the front. If you feel it in your butt, it's in the rear

Broken engine or transmission mounts?

I had this recently. Just after I got new tires. The tire jockeys balanced it and put all the weights on the inside of the rim. I guess they’re used to doing that now with all the flush faced rims they deal with. Had them balanced by someone else that was old school and they put weights on the outside of the rims as well (Fuchs 2.0L rims) and it completely eliminated the issue.

Look at Tangerine Racing under Transmission (Rear Hub Centering Ring), ths might help or resolve your problem. Mike Kelly

5 lug conversion from 4 lug?
Rear disks not centered after rear wheel removal?

after exhausting all possibilities, do check the cv axles.

tire balance
tire balance
tire balance
bent wheel
loose swing arm
cv axles