I believe it has a sterling 10.5 SRW rear end but not sure? I think it's a Dana 60 front. Rear axle is stock at this point. 33" Mastercraft all terrains.

 

Check the door tag for the axle code and give it a fierce googling. Or post up here.

Stock LS is ok (well mine is only ok) but a more effective set up is a Detroit TrueTrac. Some day when funds allow...

 

How to make it have a posi rear end....simple stick one in and be done with it (sorry I just had to)


but seriously I agree with the above post, do some research and google your door tag (VIN) and see ifr it already has one, if it does or you want better go with the true track/locker (i think thats the name)

 

Most every 4x4 that I've seen has LS diff in the rear. Is your truck 4x4? If so, then check your axle code on the door like others have suggested.

If you aren't the original owner, then it's possible a previous owner may have changed the diff lube and added some friction modifier. It's pretty easy to add too much and that could make it appear like it's an open diff.

Manual says the lube in the SRW axle is lifetime and doesn't need to changed. Some of us change it every 100k miles just for piece of mind. I changed mine at 100k and 200k and didn't get around to it at 300k. I am 25k away from 400 so I'll probably do it then. Maybe...

 

F.Y.S.A.A.R.