99 XJ
4.0L
AW4
231
Approx 107k original on the Jeep.
Have replaced all U-joints except front wheels about 6 months ago.
I can hear a little clunking sound at low speed (parking lot) Which sounds just like a failing U-joint.
I checked the drive shaft with the wheels off the ground and there was some play. I don't know how much is normal. Granted she's 21 years old, but only has 107k on the clock.
Worn splines? or ?
If I had to guess, I would say the movement before engagement with rear wheels off the ground was about 1/2" or so.
Is this normal wear for age and mileage? Something that is at the extent of needing replacement/ attention?

 

If it's only when changing from forward to reverse and visa-versa, it's probably ring and pinion backlash. Not unusual, but something to check out.

 

here is a link that shows an effective way to diagnose a worn or improperly set diff, gives a lot of detail, especially measuring the total torque to turn the assembly initially

https://www.searchautoparts.com/moto...ation?page=0,0

 

ever cleaned and lubed the splines under the boot?

 

I’d suspect U joints. Where is the play? Going into the T case or around the joints? If it’s at the joints you know your problem, if you can feel any play at the joints I’d replace them.

 

Check the u-joints to make sure you haven't lost a snap ring. That can allow the joint to push out a cap and run off center.

What Cruiser said makes me wonder. I've never done that on my WJ with 253K miles on it!

 

well sometimes we have to notice when captain obvious has entered the room. Lol
ive never done that to mine.
and yes checked them all and I greased them maybe 1,000 miles ago.

 

Thanks, awg! I bookmarked and archived that video for future reference. I knew most of the material covered in it, but having all the data in one place helps.

 

I don't want to assume because we all know what ***/u/me spells...

You're referring to the slip yoke right? I will have to see if I can loosen and move back to do that without cracking it. I'm certain it's original to the Jeep...21 years ago.
What is the best lube/grease to use on that puppy?