Loud with vibrations from the rear end (?) at 50 mph

[windsurfvan]

Acquired my 2nd van recently ... now I am a bona fide enthusiast. It really is a gem for the price i gave. It's biggest issue is that at 50 mph it gets loud with vibrations seemingly coming from the rear end. Mysteriously, it smoothes out at 60. Runs great at speeds below 50.

I trailered it home from out of my area for this reason and haven't tested it on the open road . Any thoughts or diagnosis?

[Riverology]

Check the drive shaft, similar thing was going on with mine before it failed. They can do lots of damage at higher speeds. I have an OEM one on a parts van still if you want to go that route. I put an aftermarket on mine for around $350 as they are more better.

[windsurfvan]

Check the drive shaft, similar thing was going on with mine before it failed. They can do lots of damage at higher speeds. I have an OEM one on a parts van still if you want to go that route. I put an aftermarket on mine for around $350 as they are more better.

Thanks for the great info amigo. I was guessing that it could be in the drive line. A mechanic pal down the street is going to drive it soon and hopefully diagnose it. I will update soon.

[technocj]

I had a similar issue a few years ago, changed out the u joints, no joy. Eventually I figured out it was the pass side rear wheel bearing, swapped in a used axle. No issues since. Replacing the bearings with new is the way to go, if the driveshaft proves good.

[windsurfvan]

I had a similar issue a few years ago, changed out the u joints, no joy. Eventually I figured out it was the pass side rear wheel bearing, swapped in a used axle. No issues since. Replacing the bearings with new is the way to go, if the driveshaft proves good.

Thanks for sharing info on this issue. Haven't had time to get to the bottom of this yet.When I do, i will post.

I failed to mention that the issue is with a 4wd AT van.