Quote Originally Posted by Deuce
There is a strong possiblity that these two threads are related. I have seen rear center sections make noise and vibrations. I have also seen the rear bushing in a transmission case be worn and cause the same isssues.

Sometimes a driveshaft will cause the 50 MPH plus vibration. I have removed the rear portion of the driveshaft and rotated it 180 degrees, reinstalled it and the vibration be gone.

But I believe you need another 8 inch center section


I would agree both are the same problem. Does your exhaust exit under, or behind the rear of the car? Exhaust harmonics sound very much like vibrations. Just an idea.