There is a "rule of thumb" when dealing with differentials.

If you are going to have it apart to regular, replace ALL bearing and seals within the differential.

My preference is to also relplace the outer axle seals and bearings.

I would rather start with all new than to rip it apart and replace a leaking seal or bad bearing a few months down the line.

U-joints an be replaced without disturbing the integrity of the axle and differential seals.

John Stewart
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