55+ vibration - Help

[tdangle]

New update: Since the rear end is an open diff type, I raised one side off the ground and run it up to about 50 MPH per the speedo. I know the tire is running 2x as fast. Same vibration. if I drop the speed to 25 on the speedo, no vibration. So this leads me to driveshaft speed at 50 is when vibration starts. did the same thing with a factory steel wheel, no change. Tried the other side and same thing.

Took video of the drive shaft at the trans, carrier bearing and rear axle. Nothing looked out of place.

Rear end has a weird noise especially when slowing down during this test. I starting to think something is amiss with the Dana 60 rear end. Oh and incase if was missed in an earlier thread, driveshaft has been fully rebuilt and balanced twice, once when it was rebuilt and the other when it was shortened for my new trans.