This isn't Toyota related but the Nissan forum looks dead and this one always good responses so...

A friend of mine took his 2000 Pathfinder in to the dealer to get it serviced and to get all the drivetrain fluids changed. When they drained the oil from the rear diff, what looks like a pinion tooth fell out. It's about 1" long and 1/4 inch high. It looks like it fractured right at the root.

The truck has a V6 and manual trans with about 120,000 km / 75,000 miles on it. He bought it used in 2003 and, for all he knows, that tooth was sitting in the diff form day one. The diff makes no noise and he doesn't drive it hard or off-road or tow with it. The dealer quoted $900 to fix the diff. I don't know that I would bother to fix it if I was him. Any thoughts?

Thanks.

Can you actually see the pinion thru the drain or fill holes? I remember a 60-minutes segment on a shop that was planting evidence of component failure on perfectly sound vehicles, then charging outrageous repair costs.

Probably rare, but a pinion with a whole tooth missing that doesn't make any noise sounds a bit suspicious to me.

same thing happened when i went to drain the oil out of my friend's 4.88 third in his 4runner. i was planning on installing it in my truck but needless to say i didn't use that gearset lol. his truck only had 145k on it.

i should note that he didn't know anything was wrong w/ it when the truck was in drivable condition.

I would just run it.
didn't worry about it before and it was fine. why worry now?

Thanks, that's what I was thinking. He's a retired guy who takes it pretty easy on stuff and it hasn't blown up so far. The piece looks like abouth half a tooth so there may be enough there that it's working without noise?

Those 3.3 litre V6s are pretty noisy too so maybe he just can't hear it the diff!

Regardless of what he does, it's a good thing that the chunk in out now, and not floating around in there.