Due to the nature of the center joint, there is very little rotation of the joint. For this reason, they develop wear and binding in a very specific spot. Often, you can change the movement of this spot ever so slightly and the vibration will go away.

You can do this by loosening both bolts that hold the carrier bearing mount in place and then remove the bolt that goes in at an angle. Put a washer between the carrier bearing mount and the body and put that bolt back in through the mount and the washer.

This will move the rotation off of the original position just enough to eliminate the vibration in most cases.

Good luck with it,