I too am having the same problem as "RossettiJ" the vibration starts about 65 to 70, I've changed out the u-joints,had the drive line balanced, changed out the bushing in tail shaft, tried different yokes, check the pinion,tires balancec??
The rear end is 12 bolt with 3.08 gears, hows does one check for a bent axel shaft? If you have a bent axel would it not vibrate at all speads? Could a wheel bearing be bad?
