Remember, ALL of the bearings are using the same oil...

Replacing the u-joints is a cheap maintenance step with any high mileage setup.

If you are getting leakage out of the pinion seal, consider the downstream connections -- the carrier.

When you flush, you might consider new bearings within the diff, including the pinion bearing. Especially if there is a potential for metal fragments to be floating around in the oil.

John Stewart
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