Fixing Axle Leak

Yes, you will have to unbolt the drive line. You can let it hang out of the trans so you don’t leak oil or the trans.

As for the rear end; you will have to pull the rear tires, pull the brake shoes / hardware to get to the axel holding plate that has 5 nuts to pull the axels from diff.

Now check to see what style bearings you have. Cone style bearing are stock, and cased bearing are (green bearing) cone bearing have to be shimmed correctly (as they came out) to center the axels in the housing / diff. I’d recommend to get a set of “green bearing” from @Dr Diff. (He has diff gaskets also. Might be able to get from a local trans/diff supply shop) Cheaper and easier to deal with. Will need a press and bearing remover to remove/install the bearings. But worth the cheap insurance you don’t loose a wheel bearing. Can’t hurt the check the fronts also. I was working on a Chevy 2 last week and what do ya know the front passanger inner bearing was fucked.

For the diff, unbolt the 12 or so nuts ( I’d leave one on the top stud loose until the last moment before removing so it does not fall out. The diffs weight is about 60 pounds. Once removed, scrape the old gasket off of the housing and diff. Once clean, put a thin bead of black gasket maker on the housing, then the gasket face, reinstall the diff and put on 2 nuts to sung while putting the rest of the nuts on. (Think the torque is 35 ft pounds) slide the axels in, replace gasket, axel holding plate and the 5 nuts, again 35 ft pounds. Rebuild your brakes.( you might be able to not take the brake shoes hardware off)

As for diff oil. I used redline 75/90 gl5. But you could also use any 90w gear oil. If it is a sure grip you’ll want some friction motifier in there. Fill the diff until a little dribble is coming out of the fill hole.

As a side note, since your messing with the rear end, I’d had a diff repair shop check / rebuild the suregrip. So you know you have fresh clutch plates (as I assume it’s not a cone type diff) and bearings in your diff. That way you know the rear end is all good to go for the next 50k plus miles. Also, would be a good idea to replace the u joints in the drive line. Ask me how I know. Just blew out a u joint in my front drive line of my 4x4....