97 Rear Differential Failing Repeatedly

[Cooper197]

Hey guys,
So I'm having a bit of an issue with the rear diff on my 97 L wagon.
About 10 months ago the car started making this awful whining sound. It got especially bad and I took it in and was told the rear differential was bad. It was replaced and I was on my way. Everything was fine and it didn't make any noise for about 100 miles, then it was back. Whining on acceleration and then it sounded like the car was winding down on deceleration. The noise grew louder and louder, especially if there was people in the back seat, and so I went back in. Again, the front bearing in the rear diff had failed. A new diff and all was fine...for 80 miles. The whining is back and getting louder, just as it did the two previous times. This has me thinking something isn't right. I don't know if I have an issue that is eating the differentials, or if the guy put the wrong diff in my car. I'm a bit unsure of where to start checking into, talked toa few other locals about the guy I had do the work and and quickly learned that was a mistake.

My thinking is a possible transmission issue, this seem likely?

[phi11]

Well yeah, next is center diff...

How are the tires?

[Cooper197]

Tires are pretty good. They were new last summer, which was ~10,000 miles ago I believe.

[decke48]

Pull the top plug and check level of oil and condition.. Is the guy pulling the yoke off and putting a new seal in? If so he may be over tightening the yoke crushing the "crush" sleeve to putting to much tension on the bearing.
For a failure in such a short time. Theres either an oil problem. Or a installer error.
There putting the right ratio diff in? If not its going to fry the center diff

[Cooper197]

Thanks,
I'll check into it more tomorrow. I know he filled the fluids, so that shouldn't be an issue? For now I put the FWD fuse in and it seems to be pretty quiet. In fact it's better than it's been in a really really long time. On the bill it says something about a crush sleeve or crush washer or something like that. Then again, it could have been referring to changing the oil? This is totally not my area of expertise here, I'm very willing to bet it is due to installer error or wrong ratio, but it seems like I should then have issues with the front too if it takes the center diff?