others like me just fix stuff when actually broke.

When my axle went, I was warned "better do them both, the other will break next", but I chose to only do the one side.
That was two years ago; still no issue.

The biggest deal about the job is doing it the first time. Now that I have done it, I have no issues about going in again. It is not that difficult; imo it is a harder time changing a starter than an axle, frankly.

Seals, if they are leaking, but if not.. I didn't bother. Still no leak. (i seem to recall two different types of lubricating styles on those seals, for my car at least (1980); make sure you use the right ones. Gasket sealer on the pan made life easy.

The best advice I see here is "Dont forget the spacer washers between the dif and axle"- Pay close attention to the spacing on each side.

And of course, you will be prying at stuff underneath a heavy car that needs to be properly supported to not crush you...take this very seriously.

Have fun, it feels great to save a bundle on this one!

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Think Alternative Energy!
300CD '80 (now gone but not forgotten...)