My shop just called me up and told me there was a lot of play in the rear driveshaft, and that they thought there was likely something wrong with the rear diff. They haven't done any work on it yet, and I'm reluctant to have them look further, especially if it's something I could fix myself.

I've seen some posts about the front driveshaft having play, but not much on the rear. What are the potential causes for this? Worn splines on the driveshaft? Something internal in the diff more likely? They're saying it rotates 180 degrees, which seems like a ton of backlash.

 

This is what the shop is showing me -- a bunch of metal on the drain bolt. The metal seems a bit worrying, but I'm not sure if it warrants replacing. Any thoughts? They say they can fix it with a second-hand part.




Diff overview




Metal filings

 

I should also add that I had the rear diff oil changed only a couple months ago, so it's not like this was floating around in old oil.

It seems weird that they're saying there's a lot of play in the diff, yet there don't appear to be any large chunks missing from the gears. What could account for that?

 

Im not a diff expert, but I believe that oval hole at top should be circular and that those curled up shavings next to it are from wear.

 

That can't be good if that hole's supposed to be oval. It seems like the peeling metal around that has to be a sign of serious wear.

I'm leaning toward having them replace it, although I sure hope the root cause of this wear is also addressed, assuming it's not just normal wear.

 

Abran is correct, that should be a circle.

Buy a new diff for like $75 shipped

 

New diffs cost around $1000, from what I can tell. Am I missing something?

 

Just to follow up on this, I'm getting it replaced. That wear looks scary enough not to chance it.

 

*new used haha. Plenty of used guys have them for about $75 shipped. Do not reuse that diff!

 

I've been through 2 diff so far. i just pick them up from a junk yard when i can so i always have 2 laying around for when it happens again.

Diff#1


Diff#2


And my spares i picked up at the junk yard during an "All you can carry for $60" day.