09-17-2011, 05:01 AM
My bad for coming off as an ass. I know moving your U-joints into another position will often cause vibrations. If you take the driveshaft off at the U-joint, you have to mark everything to make sure you get it back on in the exact orientation. If not it will be out of phase. I think that most likely the problem is the shaft was not balanced properly to begin with.
-chris
-chris

