I recently scavenged a 4.88 IFS diff out of a 93 4runner. It rotates smoothly but now that I've cracked it open at home, the ring gear shows some nicks on some of the teeth along the heel (exterior) edge. Maybe 1/4 of the teeth are affected.

These are small chips halfway up the heelside teeth, maybe 1 - 2 mm flakes. Two of the teeth have hairline fractures that go a bit deeper.
The meshing surface seems fine, and the pinion looks flawless.

Can I run this? SHOULD I run this? I've seen people run some pretty gnarly gears and these look better than that, but I don't know how far I can push it.

Follow-up Question: I'm planning to install it along with a freshly build 4.88 locking diff from Marlin. Do I risk damage to the rear if the front fails? I plan to get a locking front built eventually, but I was hoping to run this factory 4.88 for a year or two first.

 

I wouldn't run it.

 

That gear is primed to grenade. Junk it.

 

Daammit. Thanks for talking me off the ledge guys. Guess my new diff is gonna be sitting in the garage for a while.