loose pinion shaft/spider gears?

[R.H.T.]

Need help. I appologize if this has been posted elsewhere, but I have done several searches and have not found an answer. I have a 98 xj with rear end noise. (chrysler corp. 8.25 29 spline). A thumping in the rear consistant with vehicle speed, especially noticable while coasting and decelerating. I have made every attempt to locate the noise (including new drive line U joints) and found nothing wrong till I opened the diff. While looking things over I noticed a somewhat large amount of play in the carrier. when turning the yolk and watching the carrier center section and spiders there seemed to be a lot of play at the pinion shaft allowing the spider gear to move inconsistantly with the carrier. Sorry for the long winded explanation, I guess my question is, could this be causing my noise? or has anyone had experience with this kind of problem? It is a stock open diff 3.55 gears and 145000 miles.
Thank you in advance to anyone who can help.

 

[CartsXJ]

I had a similar problem with mine, trac-loc 8.25. Check to see if there is any play, in and out as you turn the pinion. What happen with mine is when they installed the gears the frist time they didn't set the torque on the pinion nut and it loosened up. So, if there is any play in the pinion to ring gear postioning, beside the standerd back-lash, it will make a very nice knocking noise. Another idea, is to check your ubolts. They could have become loose, as me how I know.

 

[explorer]

E- brake cables hitting the wheels?

 

[XJ_MAC]

Axle shifting/rotating up and down during accel/decel? Some is normal. Chk for excess and if it's banging Drive Shaft against the xfer case or binding the ujoints.

 

[R.H.T.]

Thanks for the feedback. I know the e-brake cables are clearing, looked them over carefully. I will go back and double check the pinion, drive line and u joints as Cartsxj and XJ_Mac had mentioned. Perhaps the crush sleeve is giving up? The patern on the gear doesnt look like the pinion is walking around though. But I am certainly no expert on this. Thank you all for your help, I'm going to go burry my head under the jeep today and try to get this worked out.
Thanks.