AWD 8.25 IFS bearing question

[Lake Tahoe]

I have a 04 Tahoe AWD and had the famous front carrier lock tab fail and pitted and wore the carrier bearings and races. I am doing a complete bearing overhaul of the diff and got everything all set up correctly. My question is are there supposed to be 2 inner axle bearings that go in the adjusters? When I took mine apart there was not one on the passenger side long axle side. I ordered a USA standard complete o/h kit and it came with 2 inner bearings, and one outer bearing that goes into the long axle tube by the seal. It also has the little bearing for the 4x4 shift fork but the AWD unit does not have that. I am trying to figure out if I need to install this other inner bearing in the adjuster or if that is for the 4x4 selectable unit. The all data exploded diagram I have is only for 4x4 not AWD and I cannot find conclusive information one way or the other. Someone has been in this unit and gone through it before me so I dont know if it was left out or not previously.

 

[6speedblazer]

Only the 4x4 diffs have a second inner bearing on the long side. Awd omit this bearing.

 

[Lake Tahoe]

Only the 4x4 diffs have a second inner bearing on the long side. Awd omit this bearing.

Thanks for confirming that for me 6speedblazer! I got the diff all buttoned up tonight. Now to reseal the oil pan before throwing it back in....

 

[6speedblazer]

Thanks for confirming that for me 6speedblazer! I got the diff all buttoned up tonight. Now to reseal the oil pan before throwing it back in....

i will say this. i installed the extra bearing to do my backlash adjustment. the tool i got to adjust backlash was made to fit that bearing. with out the bearing in the adjuster, the tool wanted to slip out. so i tapped the bearing in, adjusted backlash then pulled it back out with a slide hammer.

 

[Erickk120]

i will say this. i installed the extra bearing to do my backlash adjustment. the tool i got to adjust backlash was made to fit that bearing. with out the bearing in the adjuster, the tool wanted to slip out. so i tapped the bearing in, adjusted backlash then pulled it back out with a slide hammer.

I admire you for tackling the front end, I've done a few rear ends but the front one on these trucks would piss me off quick. Taking it apart and reassembling and then adjust depending on the bl readings, preload, and gear pattern. Thank god mine hasn't been used much offroad, Has 220k miles though so we'll see how it goes.

Can you explain how this problem happens or is it a problem from factory?

 

[Lake Tahoe]

i will say this. i installed the extra bearing to do my backlash adjustment. the tool i got to adjust backlash was made to fit that bearing. with out the bearing in the adjuster, the tool wanted to slip out. so i tapped the bearing in, adjusted backlash then pulled it back out with a slide hammer.

That may be a useful tip for others setting it up. I opted not to buy the $90 special spanner tool or get creative making my own. I just simply took a baseline measurement and then loosened the case enough to remove the carrier preload and adjust it by hand until the backlash 'felt' good, then a few more fine tune measurements and I got it in spec at .0045 backlash. Its a few more steps of course but for the extra 15 mins of fudging around I'll put the money back in my pocket

 

[6speedblazer]

I have built enough front diffs to knows its impossible to set them up correctly without the proper tool. You do more than just adjust backlash. You are also setting carrier bearing preload with the tool. Thats the most critical measurement there, seeing as how most of these are rebuilt due to bad carrier bearings.

 

[M1Gunner]

My carrier bearing outer races were toast when I rebuilt my front diff

 

[Lake Tahoe]

I have built enough front diffs to knows its impossible to set them up correctly without the proper tool. You do more than just adjust backlash. You are also setting carrier bearing preload with the tool. Thats the most critical measurement there, seeing as how most of these are rebuilt due to bad carrier bearings.

This is true but isnt that measured by the final turning torque of the assembly or am I missing a step in there somewhere? I think I am at 42 or 44 inch lb turning torque of the ring and pin assembly which is within the 30-55 spec.

 

[6speedblazer]

when the case halves are together you have to set the backlash adjusters for carrier bearing preload. which i believe is 55 ft/lb for new bearings.