Pulled the diff back out and apart. I remember why I hate doing pinion seals. What a bear to pull the yoke off the damned things. After pressing the pinion out it was obvious that the rear bearing was the noisy one. It wasn't likely to fail any time soon but the wear on it was obvious and enough to explain the noise.


The front bearing race is easy enough to knock out but there isn't enough purchase on the rear bearing race to get a punch on it. Ended up welding a couple blobs onto the race to get some meat to hammer against. It came out easy enough. New races went in without any hassle. Rear bearing pressed onto the pinion followed by the tone ring for ABS. Front bearing and spacer went into the case before the pinion seal. Then the whole stack was put in the press to push the yoke on enough to start the nut. Using the impact I snugged it down until a bit of resistance was felt. When I first spun it, about 30% of the revolution felt like it was binding. My heart sank but I quickly realized that the pinion seal needed to sit a bit less than flush to prevent interference with the yoke dust shield. After using a drift to seat it further the pinion spun nice and free. I kept impacting in short bursts and checking the resistance to turning. It quickly went from very loose to just right. I didn't measure it beyond a calibrated feel, but it very closely feels like the previous measurement, actually measured. I double checked the position to my measurements prior to disassembly and it was spot on. LSD carrier went in, and side caps torqued. One thing jumped out to me right away. Upon turning, the diff now coasts a bit where previously it stopped almost immediately. The quaife is 12 lbs heavier than stock and should coast with a bit of momentum... and now it does.

Back in it goes, I'm getting pretty quick at that. After filling with gear oil....again :rolleyes: I spun it up on the lift. Success! Drove it home, about 5 miles and it sounds great. Now if it just stays that way I'll call it a win.

Lesson learned.... don't think you can get by only doing half the job. If you're gonna have one apart, you really gotta go all the way.

I thought the explanation pointed to pinion bearings. At least its done now

Then there is me, I got my diff from a Junk yard and thought, I have no history on this so I better replace all the bearings. and of course when I pulled them out they all looked perfect.

Glad to see you got it going hope it stays quite.

Happy to report the diff is still working great. I'm calling it good.:cool:

As a followup on this thread I'm posting pictures of all the bearing numbers for reference.

Typed the numbers so others can search

Side bearing , cone M806649 Timkin

Side bearing , race LM806610 Timkin


The fronts are probably special made for MB given how thick the race is
Front pinion bearing , cone BT1B 329120/ Q SKF BRAND

Front pinion bearing , race M86610/2/QCL7C SKF BRAND


Rear pinion bearing , cone 4T-M80204BV3 ? brand

Rear pinion bearing , race 4T-M802011 ? brand

I'm fairly certain they were also SKF