What a failed diff looks like inside.

[Chris]

This diff has almost 245k miles on it, toward the end of it's life was making a terrible whining noise.

Here's what it looks like inside.

Ring gear:

They should be a uniform colour and surface across the gear face. Not discoloured scratchy looking.

Spider gears:

Those have obvious wear issues just looking at them. I'm surprised it didn't make really bad noises when turning.

And a bad pic of the pinion. It's discoloured and looks much like the ring gear. It was hard to get a picture of without full diffassembly:

 

[jaKe]

that's nothing, still has all its teeth.

 

[IBratmanI]

Looks a lot better than many I have seen, and those were quiet! I still haven't seen one fail in an N/A. The R160's really are tough! But at least this solved your noise issue.

 

[Chris]

The one in my GL was making bad noise in 4wd too. I guess when they have lots of miles, they give up.

 

[IBratmanI]

Nah, they just make noise. They rarely give up. I have a diff over at my buddy's house I still have to go get!

 

[Chris]

They make more and more noise until it pisses you off enough to change it. I haven't heard of anyone running one long enough to seize, or whatever.

Unless it runs out of oil. Someone on USMB had theirs leak out on the highway and seize. But as long as they have oil, they'll just whine.

 

[IBratmanI]

Yep, no oil would do it for sure. Just pretend you have straight cut gears for high HP yo! Haha

 

[Mighty Subie]

Meh. Not that bad. I wouldnt call it a failed fear diff. I would call it a worn diff. Failed generally means chunks fall out or just one big melted mess

 

[Chris]

Worn out, failed. Sorta the same thing. I like every part on my car to be in good mechanical condition.

If something is going bad, even if it has thousands of miles before it'll totally leave me stranded, I replace it. Mechanical problems bother me, so I fix them as soon as I can.

 

[Mighty Subie]

I agree with you there. I just think of the word failed meaning catastrophic failure.