In my case, I had other things going on with the diff bearings due to rebuild and LSD installation errors by the supplier. However, when I removed the solid diff bushings and went back to the OEM diff bushings most of the diff noise went away. Problem mostly solved.... Ultimately, the diff had to be rebuilt as well as the ring and pinion backlash reset by a local repair shop. Here's a link to that thread.
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HELP - Modulating Whirring Sound From Diff or Rear End Area???
https://www.m3post.com/forums/showthread.php?t=1540429
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