Hello. Just wondering how hard is and expensive is it to replace this if needed? Thank you in advance.

Has the backlash opened up? High mileage?

You can throw a bearing in it with a new crush sleeve pretty cheap. Under a hundred doing it yourself. Rear diffs are not conducive to being patched though.

Rear end has around 125k miles on it. I'm not sure for the backlash. It's on a truck I'm looking at currently.

I changed the pinion bearing and race in my 94 Ram 1500. The race and all the rollers were pitted and was causing a rumbling sound. I did it in my garage on jack stands. The only hard part was crushing the new crush sleeve. I finally just put the old one back in and ran it. It was still working fine 70,000 miles later when a tree fell on it and destroyed the truck. I think the cost was less than 50 bucks or so, but it's been a while.

My friend recently acquired this Ram 1500 with a similar rumbling sound. The previous owner thinks it's the pinion bearing. Got to finish installing the rotors and method wheels on the Silverado this week before we can take the Ram in. We'll see.

This has happened 3 times on my 1995 Ram over 190,000 miles.

The first time at a bit over 60,000 miles the regional Chrysler rep offered to pay half the cost when I complained, hinting that it was a well known defect.
I used the opportunity to also switch to 3.21 diff gears from 3.55 on the 9.25 diff.
This improved steady highway speed MPG, and made 2nd gear more effective towing trailers up steep grades.

After the 2nd time I wanted to know “why are the bearing and seal not lasting 200,000 miles” ?

It took awhile but I eventually concluded “The Crush sleeve continues to crush more” causing early failure.

Use a hardened steel sleeve and spacers to get the proper dimensions inside the diff.

Please be aware that in the meantime Chrysler abandoned the tapered roller bearings in the original design 9.25 diffs to go to lower friction heavy duty roller bearing, which give a slight MPG improvement.

It should be more widely known that 2.76 diff ring and pinion gears have lower friction than higher gears like 3.92, 4.56, etc

It should be more widely known that “straight cut” ring and pinion gear are noisy but have lower friction.

It should be more widely known that the number of teeth on gears should be “prime numbers” to reduce both wear and noise.

It is thought provoking how prime numbers ( 3, 5, 7, 11 onward to infinity) pop up in best gears, fan blades, hard to break codes, and Bitcoin.

What year did the tapered bearings go away? My 99 Dakota still had tapered ones.

I rebuilt mine using the shop manual, it wasn't hard at all. The threaded adjusters make setting the lash pretty simple.

Thank you again everyone.