Re: Noise in front diff
did you look at the pinion bearings?
Realistically, I have overhauled a number of differentials that were making all kinds of noise, and it was not uncommon to not find any obvious damage to the bearing races, well nothing that would explain the horrible noise that was being made. If the noise is coming from the front and changes pitch with load I would say your noise is going to be in the front diff, is it a higher pitch noise? your pinion is going to spin faster than your ring so it typically emits a higher pitch noise with bearing failure.
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