Don't bother to remove the cover. Put it in neutral in a safe way so the you can get under it without danger and see how much play there is in the pinion gear....if its more than about 1/12 of a rotation you have a lot of wear.

The diffs almost never cause trouble. I would look at the half shafts for wear. The cv joints last a long time but they eventually wear out and need to be renewed.....could be anywhere from 100 thousand to three hundred thousand miles depending on usage.

Good luck

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.