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.