Rear Diff showing signs of leakage :(

So I am cleaning all the sand off of my truck at the car wash and notice all around the differential there are signs of oil all the way around it. Not good.

What Fluid do you recommend? Is this a DIY, or am I going to have a carrier fall in my lap when I pull the cover off:frown: ?

It is a 2wd, 5.3, 2001 LS, Tow pkg, yadda yadda.

I really need to do this this week before our new baby gets here next tuesday!! (no tinkering for me for a good while)

That should have a standard 8.5" Saginaw rear axle in it, similar to what's in my car.

The cover gasket can be replaced (on mine, I use "The Right Stuff" by Permatex in lieu of a gasket), and the front seal can be replaced. You will need a 1-1/4" socket to remove the pinion nut. When you put it back together, use a new nut and torque the nut to about 15 - 25 lb. ft. only so as not to upset the bearing clearance. You shouldn't concern yourself with the nut backing off - it should have Loctite on it (that blue stuff), plus it's a crimped nut. You will need to take the driveshaft off - and once you get the yoke off (a small mallet works great for knocking it off - it's only a light 'press on'), inspect the sealing surface for grooving, and replace the yoke if you see any no matter how light it might look. Replace the seal, too.

The front looks ok, and I am in a time crunch. Its the rear seal thats leaking.

Is there a gasket there from factory or did they silly-cone it?

There should be a gasket, at least our 2002 has a gasket on it. ;)

To answer a question that I missed with my first reply, I'd use 85w-140 limited slip compatible gear oil.

There should be a gasket, at least our 2002 has a gasket on it. ;)

To answer a question that I missed with my first reply, I'd use 85w-140 limited slip compatible gear oil.

Thanks a lot, is it a DIY job, or should I let a dealer do it? ALso what are the torque specs for t he bolts when they go back on? Do I use thread locker?

I just tightened the bolts about 20 ft. lb. by estimate - perhaps about double that of what you would use to tighten cork-rubber gasketed valve covers. No thread locker necessary.

It's definitely something you can do yourself, perhaps in about 20 minutes or so.

Pay close attention to any metal that might be on the magnet that's inside the cover.