08 denali awd wont move, diff fluid on the driveway

[Dswan]

I was driving g down the hwy at 60 and with out a sound acted like it went into nutral.
As I made sure it was still in drive and it was, there was nothing but coasting until I finally stopped and it made small grind for about 1 second and git it towed home n now there's some front differential fluid under the truck n that's all no tranny fluid but starts up quick but no gears just reasontly it did just start pulling a little bit towards the left if I gave it a he'll of the start taking off so I wasn't sure why n made sure not to do that cuz. Was k8nda sketchy !!

So it's a 08 denal 6.2 awd with 344,000 miles n haven't put much into it except basic p.m. n a small lift kit n level kit that's all
So I did notice the stub/drivers side of the front diff seemed to be about 2 in away from the diff n the long shaft/pass side was very snug up to the diff
So what's everyonse thoughts about how to fix cuz I'm in Minnesota n winter's coming quick and b4 I know it's going to be -35 outside here

 

[Geotrash]

I was driving g down the hwy at 60 and with out a sound acted like it went into nutral.
As I made sure it was still in drive and it was, there was nothing but coasting until I finally stopped and it made small grind for about 1 or 11/2 second

If you lose any component of the drivetrain (either F or R diff or the TC), the AWD Denali won't move. Since you see and smell front diff fluid, my best guess is a broken pinion or ring gear up there. Can you get any photos?

 

[Dswan]

If you lose any component of the drivetrain (either F or R diff or the TC), the AWD Denali won't move. Since you see and smell front diff fluid, my best guess is a broken pinion or ring gear up there. Can you get any photos?

This is looking up at the drivers /stubby side

If you lose any component of the drivetrain (either F or R diff or the TC), the AWD Denali won't move. Since you see and smell front diff fluid, my best guess is a broken pinion or ring gear up there. Can you get any photos?

Thus is the drivers side front diff

If you lose any component of the drivetrain (either F or R diff or the TC), the AWD Denali won't move. Since you see and smell front diff fluid, my best guess is a broken pinion or ring gear up there. Can you get any photos?

 

[blackelky]

344k ? That's amazing

 

[Geotrash]

This is looking up at the drivers /stubby side

Thus is the drivers side front diff

Your pictures didn't post. :-(

 

[Fless]

Your pictures didn't post. :-(

You don't see the Ninja at night pic?

 

[Geotrash]

So I did notice the stub/drivers side of the front diff seemed to be about 2 in away from the diff n the long shaft/pass side was very snug up to the diff
So what's everyonse thoughts about how to fix cuz I'm in Minnesota n winter's coming quick and b4 I know it's going to be -35 outside here

This is new information since your initial post. Thanks for adding it. If the axle housing of the half shaft is separating from the differential such that the has shaft isn't being driven, then that would cause the truck not to move.

 

[Dswan]

 

[Geotrash]

View attachment 415699

Yep, that's your problem. There is supposed to be a keeper on that shaft keeping the flange in position right up against the side of the diff, but the pulling stress of the front level/lift may have put enough stress on it such that the keeper couldn't hold it in position any more. You probably have a damaged seal now as well, hence the leak. You need to get that stub shaft the rest of the way out, install a new oil seal, inspect the end of the stub shaft where the keeper sits and make sure it looks intact. You could also replace the front diff with a junkyard unit as long as you have the axle ratio from the code listed on the label in the glove box. If you post a picture of that label here, we can tell you what you need but I'm 99.99% sure you have a 3.42 ratio since it's a Denali. If you replace the diff, it needs to be an AWD unit from a Denali or Escalade unless you want to make some modifications to it. Not a hard job to swap it out but a cheap Harbor Fright transmission jack will make it easier.

 

[swathdiver]

Just get a used one from LKQ or some other salvage yard. AWD front differentials ARE different from 4x4 front differentials.

At 17+ years old, the two differential mounts are likely plum wore out as well.