New pinion gear only available anywhere?

[myredracer]

Have been chasing a bad noise in the drive train in our '12 Sierra 2500HD for a couple of weeks.  Had the transfer case out and found a bad input bearing which I replaced (plus seals). I reinstalled the transfer case and still had the noise. 

 

Today I found the small end of the shaft on the pinion gear is badly damaged (spalling) which damaged the bearing too.  Diff. is a 10.5" 14 bolt 4.10.  There's nothing wrong with the teeth on the ring gear that I can tell visually.  Are only ring & pinion sets available or is a pinion gear/shaft only available somewhere?  I'd rather replace just the pinion gear (along with new seal, crush sleeve, etc.) or is that normally not advisable?    I don't want to get into setting up a ring and pinion but I guess I have no choice now regardless.

 

Thanks!

Edited November 24, 2019 by myredracer

[Formulabruce]

The ring and pinion are made together. You can use a crush sleeve eliminator, but you will end up taking it apart many times to get the preload correct. Youll need to hog out your pinion bearings to use as set up bearings. I wonder why the front end of the pinion was damaged?  lack of lube? Once you change the pinion, you will need to reset the depth and get your pattern. It might be super close if you buy a GM ring and pinion set . Maybe GMpartsdirect.com  ..

Edited November 24, 2019 by Formulabruce

[davester]

I would assume that whatever ring&pinion gear set you get, you'll need to completely set it up to get the correct pattern.  It's way cheaper and faster to do it right the first time, than to have to do it over.

[myredracer]

We bought the truck used last summer and don't know the history other than it belonged to a land surveyor company.  I think the fluid level was low (I didn't measure it) or never changed (it was rather dark).  The tranny and transfer case fluid levels were maybe  around 1/2 of what it should have been.    Good idea on checking with GMpartsdirect.  I saw a R&P set on Amazon for $185.

 

I'm wondering if maybe I can just put it all back together and take it it to a tranny shop to get set up right.  I have the fluid to check mesh pattern but no dial indicator.  Seems like having to play with different thickness shims could be a PITA.  We use the truck mostly to tow a 7K lb travel trailer and I want to make sure it's set up correctly.

Edited November 24, 2019 by myredracer

[SierraHD17]

10.5" full floater has no shims except between the pinion snout and the main housing to set pinion depth.  You remove the snout and change the pinion and all bearings out of the rear end.  The side to side adjustment on the carrier is 2 adjusters that screw in and out of the axle tubes.