Scooterpookin

1999 xj rwd

replaced both of my u joints today and noticed a slight noise reduction but not what I was hoping for,
the rear part of the drive shaft that connects to the differential moves up and down now. The side to side where the straps bolt in don't budge but the other part has a slight bit of play is this normal??

Scooterpookin

I'm thinkin that I might try and hit in those sides a little more to sandwich it more and remove the play.

PatHenry

There definitely shouldn't be play.

Assuming that the u-joint is the correct one and the play isn't in the the yoke ears, the only thing I can think is that you lost some of the needle bearings.

Edit - looking at your picture again, actually I think it may be a case that the clips are not fully seated.

Scooterpookin

Yea they just needed to pounded a lil more on those sides. No more play out of the u joints.

the next thing is I'm still getting the noise. It's not quit as loud. Most of the research I've found is that the differential is old an the bearings inside could be going. When I'm driving it sounds to me that the sound is more right behind me. Like at the front of the driveshaft I replaced that u joint too. I haven't tested up on jacks stands yet to see if I can pin point the sound. Start right around 20mph

caged

looks like you have a pinion seal leak. have you checked your fluid level, or inspected your rear gears?
chances are, you have a bad pinion bearing.
i would pull the cover and clean with brake clean so you can get a good look at condition of your oil and ring gear.
maybe pull your old seal out and replace it with a nice new one. clean your diff with brake cleaner and a wire brush.