Okay so I have a '91 XJ Laredo and I just changed the brakes all the way around because of a grinding noise in my rear. Thinking I fixed the problem because of a cracked brake shoe, it popped up again. Now this only starts to grab or grind after about 15-30 minutes of driving and at slower speeds(i.e. driving down residential streets or parking areas) and it feels like my rear end is grabbing up or grinding something. Any ideas?

 

Have you checked the fluid level in your diff? maybe the gears are gtting hot because its low on fluid?

have you pulled the diff cover to check the spider gears and the condition of the carrier bearings?

 

I'm gonna pull the diff cover today and update to see what I find, but when I checked the fluid level, it was full.

 

sounds good, easy way to check carrier bearings it to pry between the diff housing and the carrier up,down,left,right there should be very very little to no free play.

post back what you find =)

 

That's one of the typical and common symptoms of the additive wearing out. LSD's need that to keep them from sticking together.
Before tearing into it - try adding a tube of LSD additive - $ 10 or so.

It wears out in about 80 to 100k miles.

 

So I took the diff cover off finally (little delayed) and nothing seemed loose or broken so I just resealed the cover, changed the gear oil and added the LSD additive and haven't heard and noise yet. Thank you!