[silver_pilate]

Well, I've got the same vibration. Anything above 80-85 mph and it starts to shake. When I let off, it's worse until I slow down below the above speed.

I've got several suspects. It is definately not rpm related, just speed related, and it seems to have begun soon after I had the tranny rebuilt. I'm guessing possibly an internal balancing problem. It's not the converter, and it happens in 3rd and 4th gear. I also suspect maybe the old drive shaft I've got. I read somewhere that the hollow shaft is lined with rubber to absorb vibration. As this gets old and dries out, it is possible for chunks to break off and unbalance the shaft. I've replaced U-joints and it didn't help. Also, I just replaced my old drag radials and had all the tires balanced, and it didn't help.

I haven't really suspected the gears because I've had them for over three years and this problem only began about one year ago. Also, the noise from them hasn't changed significantly.

The tranny is under a three year warranty, so I'll probably take it back and have them go through it. Maybe they can check the balance of the drive shaft as well.

--nathan