pipefitter

I have a totally stock '96 4x4 automatic with around 123,000 miles. I recently put new tires,(Sumitomo Encounters), on it and had a bad vibration that came and went. The steering wheel had no vibration at all, everything seemed to come from the rear. Had them re-balanced, and still have a vibration, but not as bad. The center bearing has a bit of play in it, (maybe .25"-.5"), and I wondered if that could be part of the problem.

patdaly

The carrier bearing is rubber mounted, and usually when they start a vibration, it just stays and gets worse.

I would look elsewhere, perhaps move the tires front to back and see what that does?

pipefitter

I've tried that, but it didn't change too much. I have a friend that does front end and frame work. He's going to take a look at it after the 1st. Any idea how much play is too much in the center bearing?

gorms

Well any play in the bearing itself means replacement time, but it is normal to be able to move the bearing within the rubber insulator a bit by hand. See if there are any weights on the driveshaft, if not they may have fallen off.

pipefitter

Thanks for the reply. On mine, the rubber insulator actually moves around inside the bracket.

patdaly

It's time for replacement......

pipefitter

I don't suppose anyone knows right off hand if I should have a 1.3", or 1.5" diameter shaft. I don't see any way of measuring it without removing it. Planning to replace both universals, and a transfer case seal at the same time.

gorms

It's the bigger one.

pipefitter

Well, I've replaced the center bearing, and all 3 universals. The shaking is still there, although better. I took it to a suspension guy and we went all over the truck, finding everything in good shape. My shocks however, are shot. Really shot. Both fronts are actually broken, the rears almost as bad. He said if the shocks aren't the culprit, the tires are out of round. I've ordered new shocks.