Maybe the trans mount?

 

Have you tried to jack up the rear end and put it in gear just to see if it does it with no load?
Try that and have someone watch the drive line under there and see what shakes.


Rye

 

Ok guys my reply back, I found out the viberation in my steering column, When my car is in drive as well, I checked the motor mounts, They are basically shot they are torn almost down to the bolts, The passeger side mount is torn more then the drivers side, I gotta start on that job.

Thanks 4 youre guys tips and help.