Just recently my 2000 Cherokee's rear axle started making a thumping noise. I didn't drive on it very long (less that 2 minutes) once it started.

The noise was coming from the pinion yoke so I investigated that first and found that the bolt holding it in had become loose enough for me to turn it with my fingers. I tightened it back up properly and the noise was still there.

I'm assuming that means I'll be replacing all the bearings and seals in the axle and differential. Is this a common occurance? I've never had an issue like this with my other Jeeps that had the same type of axle.