Until yesterday, I had a vibration at 65 mph and above. After reading up on the subject, I suspected the flex discs and center bearing. Turns out the front flex disc had a crack between two of the bolt holes, and the center support was dried out, weak and cracked. I replaced both parts, put it back together, and went for a test drive. Now, no vibration at all even up to 90 mph. However, starting at about 60 mph there is a hum or whine. It gets louder when I hit the gas. Any ideas? I tried to mark and realign the driveshafts as best I could, but maybe I was off by one tooth on the spline...would this cause the noise?

Rich Mayer
82 500 SL