Be careful about junkyard 8.8" axles though. One of the problems with this axle is that the pinion nut likes to back off, which can cause pinion bearing and pinion seal failure. If the axle is leaking gear oil this is almost certainly where and why. If the damage is bad enough you may end up rebuilding the whole thing. Just be careful and make sure you get a good replacement if you end up deciding to swap out the rear axle.

BTW posi-traction is a GM term, we don't use that kind of language around here.