Rear Differential Size?

[Jason in DLH]

So I’m trying to figure out what size rear diff I have. Can anyone confirm that it’s a 8.6” 10 bolt? I know it’s a 10 bolt, but I’m not sure where I need to measure.

Apparently I can find this in the RPO codes, but I’m lost...



Here’s a list of what the codes mean, but still can’t find rear diff size...

http://www.denalitrucks.com/documents/new/2007 YD printbook.pdf

I’ve got a 2007 GMC Yukon Denali.

 

[Just Fishing]

i'm curious on this as well.
I see a GU6 on your sticker, i have that one as well.
GU6 AXLE,REAR,3.42 RATIO

Eventually when i rebuild my rear end, i really want a limited slip or locker of some type...
I did see on my front axle when i had it out for the oil pickup tube o-ring job, it had a "8.25" sticker on it

 

[OR VietVet]

The GU6 is the 3.42 gears and the G80 means it has a limited slip. It is the 8.6 rear axle.

 

[Jason in DLH]

The Denali has an OEM limited slip which I’m very thankful for. The truck is a beast in the snow. Not sure why they simply didn’t add it to all versions.

 

[Just Fishing]

I have the same but lack the G80 option, is it still the same ring gear size?

 

[OR VietVet]

Yes, the size is the same at 8.6.

 

[Just Fishing]

The Denali has an OEM limited slip which I’m very thankful for. The truck is a beast in the snow. Not sure why they simply didn’t add it to all versions.

Really the only thing my tahoe was missing that i wanted, the G80.
My S10 has it (ZR2 package), Over the years i have become a huge fan.

 

[OR VietVet]

Unless you like clacking noises, the full on locker is a bit much but the limited slip does the trick.

I used to do extreme off roading and had a 73 Blazer with a one ton 14 bolt in the rear and a 1 ton Dane 60 in the front and both had 4.88 gears with Detroit Lockers in them. Yes, lots of clacking noise when really working it over rocks or some extreme trails.

 

[Jason in DLH]

The GU6 is the 3.42 gears and the G80 means it has a limited slip. It is the 8.6 rear axle.

Great, thanks! Mine is all rusted (got WD40 rust *********** spray soaking in the bolts now) and plan to replace it with a new gasket, bolts, and cover.

 

[OR VietVet]

No problem. Make sure the surfaces are completely clean and dry when put back together and just use a very thin film of sealer on both sides of the quality gasket on reassembly. I like to let sit for about 1 hour after installing bolts, before I refill the diff.