Topic: Differential trouble, advice needed

[toyodaaddict]

I need some advice on how deal with a noisy rear diff.  Toy 8" Yukon 5.29's, spool/solid spacer, built about 7 years ago.

My truck was down for a long time for an engine rebuild/overhaul. When I got it back on the road I started hearing a faint"whistling/whining" noise. Over roughly 1200 miles the noise slowly got louder and I decided I needed to fix it. I put the truck on stands in the garage. It sounds pretty bad when your under the truck listening to it, more of a howling rumbling noise than a whistle. Obviously the rear 3rd member

I pulled the diff and was shocked to find that my oil appears water contaminated ( light chocolate milkshake color). There was a fair amount of heavy metal powder on the drain plug, more than normal but no chunks. When I turn the pinion flange it feels kinda rough and hangs up a bit here and there.  To my untrained eye there is nothing obvious wrong with the gears, like chips or missing teeth.

Should someone that knows what they are doing be able to tell me if my gears are ok? I'm hoping I can just have the bearing replaced but I dont want to end up with noisy gears.

How should I go about dealing with this?

[OVRAROK]

sounds like a pinion bearing is on its way out

[toyodaaddict [OP]]

sounds like a pinion bearing is on its way out

I'm guessing your right about that.

Do you know if there is any way to be reasonably sure the gears haven't been damaged before I throw a bunch of money at it?

[OVRAROK]

I'm guessing your right about that.

Do you know if there is any way to be reasonably sure the gears haven't been damaged before I throw a bunch of money at it?

is the third out of vehicle? if so, youll have to go one by one, checking teeth, id wipe clean, take a close look. repeat

[toyodaaddict [OP]]

is the third out of vehicle? if so, youll have to go one by one, checking teeth, id wipe clean, take a close look. repeat

Yes, the third is on the bench. Trouble is I don't know what to look for other than broken/chipped teeth. I have no experience working with gears.

 I took it to a shop and they said they could put new bearings in it but I dont feel like they took a very good look at it.

[OVRAROK]

Yes, the third is on the bench. Trouble is I don't know what to look for other than broken/chipped teeth. I have no experience working with gears.

 I took it to a shop and they said they could put new bearings in it but I dont feel like they took a very good look at it.

if the shop is reputable, more then likely there no visible wear, did you ask them to look at the gears. if there's no obvious chunks, slap some bearing in it and run it

[toyodaaddict [OP]]

if the shop is reputable, more then likely there no visible wear, did you ask them to look at the gears. if there's no obvious chunks, slap some bearing in it and run it

No, no obvious chips or chunks. 

I did ask them to look at the gears but I wasnt familiar with the guy that was helping me. He didnt look at the third very closely. He more or less said they could replace the bearings and see what happens.