Rebuilt both axles still have a vibration
 

Okay here's the scenario; I had two broken CV joint bolts that caused a severe vibration at low speeds, 25 MPH and above. This weekend I rebuilt both axles; replaced all 4 CV joints, new boots and all new bolts. I took it out today for it's first drive at speed and at about 70 MPH I have a similar vibration, but not quite as severe. I feel it right under the drivers seat. BTW the two broken bolts were drivers side at the wheel hub. Could this be something as simple as a tire out of balance? I brought it home and rechecked the torque on everything and it was all in spec. Also, I only drove approx 3 miles after I felt the initial vibration of the two broken bolts. Any help is greatly appreciated. THX

I can't help with your vibration, but for the record: a transaxle is not the same thing as an axle. A transaxle is a combined transmission and differential, like our 911's (and many FWD cars) use -- in your car it's the 915.

Nit picking finished. ;)

I'd check the balance on all four wheels, or swap in four known good ones from a friend's 911. Trouble in the front can feel like it's coming from the back.

It could also be a bent axle.

Thanks for your reply Jack! Sorry for my lack of technically or mechanically correct terminology. You can't tell this is my first 911, can you? I'm actually quite embarrassed as I've owned several hot rodded bugs. Anyway, I'll try the balancing on the the tires and see what happens. The original problem "two broken bolts" brought on a feeling of a wheel coming off due to loose lug nuts or a tire going down. I've checked all of my tire pressures and they're all in spec as well.

broken CV bolts also
 

Chris,

Have you found the cause yet. I'm having the same problem.

Guy
82 SC Black Coupe