Rear-end swap: 8.6" 10 bolt w/3.08 >> 9.5" 14 bolt w/3.42 + 3.42 swap in 8.25" front (or else)

[5StarCustmSolutns]

I'm confused. As far as I know, the 9.25" rear diff with the 6-bolt wheel hub flanges only came on 2WD half-ton Escalades and Denalis because of the higher torque output of the 6.2. If that's true, then I wouldn't expect there to be any front diff in that donor truck. Are you sure that the rear axle you're about to pick up has the 6-bolt hub flanges and came out of a 2WD Escalade or Denali?

And to answer your other question, no, a 9.25" front diff will not fit under a half-ton Avalanche, AFAIK.

I'm confused. As far as I know, the 9.25" rear diff with the 6-bolt wheel hub flanges only came on 2WD half-ton Escalades and Denalis because of the higher torque output of the 6.2. If that's true, then I wouldn't expect there to be any front diff in that donor truck. Are you sure that the rear axle you're about to pick up has the 6-bolt hub flanges and came out of a 2WD Escalade or Denali?

And to answer your other question, no, a 9.25" front diff will not fit under a half-ton Avalanche, AFAIK.

Thanks for weighing in... I had to delay going to get the axle a few hours to help procure lodging at Snowshoe for the Wounded Warriors Snow Day event we're helping with 3/2-3/5. I've been playing role of reservation coordinator for last 2hrs lol...

Im not 100% it will be the same donor vehicle for the front and the rear? He made it sound that way, however mostly what I heard was that I would get to help pull, and that I would get to see odometer and condition of vehicle with my own eyes!
I did call him back about 830 and ask again about the 9.25 fitting in my truck, and he said yes. He said I was overthinking it. Said Yukon XL, Burban, Esc ESV/EXT, and Av are same chassis. Said take pics of mine to compare, but it will work... I guess we'll see here in a few hours

 

[5StarCustmSolutns]

sort of... 2010+ 2500hd axle pretty much bolts in. wouldnt call it a direct swap though
View attachment 392075
View attachment 392076

This the front diff you got the Cognito spacers for? I went back and Re-read that thread this morning. When I read it the other day I didn't catch that it was 2010+ 2500. Was it a Silverado/Sierra? Is it a 30 or 33 spline?

edit- and is it AWD or 4x4 hi/lo

 

[randeez]

This the front diff you got the Cognito spacers for? I went back and Re-read that thread this morning. When I read it the other day I didn't catch that it was 2010+ 2500. Was it a Silverado/Sierra? Is it a 30 or 33 spline?

edit- and is it AWD or 4x4 hi/lo

yea silverado/sierra 2500/3500,
spline - inside the diff i think are 33? but doesnt really matter youre connecting to the 8 bolt axle stubs.
the 8bolt complete cv axles are 36 spline iirc. cant use them on 1500s or pre-2010 2500s, however gmt900 and pre2010s are same size and both 33 spline at the wheel hubs

and i dont mean 8bolt wheel hubs...connecting to the stub shafts are 6 hole for 1500, 6 bolt for pre2010 2500+ (larger than 1500) and 2010 HD+ are 8 bolts

so you need the 8 bolt inner cup to the 33spline outer.

oem axles you can pull the cv joint off the outer side of both pre/post HDs and swap them making a longer axle with oem parts.
aftermarket axles you cannot swap the cv joint, but you can swap the inner "tripod" cups between the two, but axle shaft between the two is shorter
spacers may not be needed if you use the longer 2010+ shafts and swap the outer joints onto them, but at the time i was only buying aftermarket axles and couldnt so they were short. wasnt looking to spend $300+ on each axle (x4) for oems just to see if it would even work

or call RCV and confuse the fck out of them and they will send you a set after a few tries for $2800 bux

 

[5StarCustmSolutns]

90 minute drive to salvage yard and THERE WASNT ONE 9.25" FRONT NOR ONE 9.5" REAR axle at this place... Despite the fact that I talked to dude 5 times this week, including twice this morning, each time making it crystal clear what I was looking for.....smh

The only thing that kept me from going ballistic was the 77k mi 8.25" w/3.42's in it... Only had 77k miles and was 1/3 the cost of the unit I bought yesterday. It was a good deal but not good enough to make me forget what stupid is..

 

[5StarCustmSolutns]

I'm confused. As far as I know, the 9.25" rear diff with the 6-bolt wheel hub flanges only came on 2WD half-ton Escalades and Denalis because of the higher torque output of the 6.2. If that's true, then I wouldn't expect there to be any front diff in that donor truck. Are you sure that the rear axle you're about to pick up has the 6-bolt hub flanges and came out of a 2WD Escalade or Denali?

And to answer your other question, no, a 9.25" front diff will not fit under a half-ton Avalanche, AFAIK.

Can't remember who it was,

I'm confused. As far as I know, the 9.25" rear diff with the 6-bolt wheel hub flanges only came on 2WD half-ton Escalades and Denalis because of the higher torque output of the 6.2. If that's true, then I wouldn't expect there to be any front diff in that donor truck. Are you sure that the rear axle you're about to pick up has the 6-bolt hub flanges and came out of a 2WD Escalade or Denali?

And to answer your other question, no, a 9.25" front diff will not fit under a half-ton Avalanche, AFAIK.

Last week while I was reading through one of the threads on here about this axle swap deal, someone(and I just spent about 20min trying to find it)said something along the lines of "make sure the 14 bolts you're looking at buying are not 8.6 3.42 10 bolts being passed off as 9.5 14 bolts". I thought it might've been you? possibly @OR VietVet or @CaptainAmerica1 ?? Either way you've all probably read it at one point....but I remember thinking how could that ever happen? Well, yesterday I saw exactly how. When the yard owner is telling you a ____ is a ____ when it's really a ____. If you don't know your stuff, it's real easy to either roll right out of there with a ____ thinking you've got a ____! Or convince yourself that a ____ is good enough and settle for what's avail.. Then when/if you do figure out that the heat and pressure broke you down, you end up ____ ____ ___ ____ _____'n all the way back to the ___ ___ salvage yard hoping you can still return your part...

Thanks to the foundational work all you guys put down, I was able to hold my ground yesterday....even eventually got a "you were right there is another 3.42 option" out of the guy....

@randeez, @Dantheman1540, @Trey Hardy, @swathdiver , and everyone else who's been a contributor to these axle thread

 

[randeez]

90 minute drive to salvage yard and THERE WASNT ONE 9.25" FRONT NOR ONE 9.5" REAR axle anything at this place... Despite the fact that I talked to dude 5 times this week, including twice this morning each time making it crystal clear what I was looking for.....smh

The only thing that kept me from going ballistic was the 77k mi 8.25" w/3.42's in it... Only had 77k miles and was 1/3 the cost of the one I bought yesterday. It was a good deal but not good enough to make me forget stupid

What year are you working on? Cause I don't think those front axles are for an 07+, the tab on the top is how they mounted up to 06 (07 classic trucks) gmt800s. Gmt900s have two mounting holes right next to the stub shaft on diversside

 

[5StarCustmSolutns]

What year are you working on? Cause I don't think those front axles are for an 07+, the tab on the top is how they mounted up to 06 (07 classic trucks) gmt800s. Gmt900s have two mounting holes right next to the stub shaft on diversside

View attachment 392139

Mine 2011.... Both those are 8.25's.

Not sure what year the one missing it's long tube flange came off of? Didn't see donor. Part was on shelf. Only bought because it was the closest 3.42 to me and literally had to go right past that yard Tue. Also, assured I could go ahead with rear swap and not worry bout having to roll 4x2(in Feb) until I found a 3.42 front. It was the $300 one, gonna return it.

The fully intact(better pic here) one came out of '08 Burban. Was still in truck yesterday. It was only $100.00, and we had just driven 90min to get a 14-9.5" w/a 9.25" IFS that ol dude told me was there, on his Chevy only yard.... only to find out he didn't even know they existed.

I think it just upside down compared to your pic??

Paid $243.80 w/core for 123k mile 14 bolt rear today. It's 150mi away in KY, across river from Cincy. Leaving about 930 or so to go get it.

 

[swathdiver]

Paid $243.80 w/core for 123k mile 14 bolt rear today.

Core?

 

[randeez]

Mine 2011.... Both those are 8.25's.

Not sure what year the one missing it's long tube flange came off of? Didn't see donor. Part was on shelf. Only bought because it was the closest 3.42 to me and literally had to go right past that yard Tue. Also, assured I could go ahead with rear swap and not worry bout having to roll 4x2(in Feb) until I found a 3.42 front. It was the $300 one, gonna return it.

The fully intact(better pic here) one came out of '08 Burban. Was still in truck yesterday. It was only $100.00, and we had just driven 90min to get a 14-9.5" w/a 9.25" IFS that ol dude told me was there, on his Chevy only yard.... only to find out he didn't even know they existed.

I think it just upside down compared to your pic??

Paid $243.80 w/core for 123k mile 14 bolt rear today. It's 150mi away in KY, across river from Cincy. Leaving about 930 or so to go get it.




View attachment 392237

Got it, think you're right

 

[5StarCustmSolutns]

Core?

$150 + $80 core + tax =$243.80. Bessler Auto Salvage Wilder, KY found on car-part.com

Quoted me $235 w/3yr unlimited mile warranty. I figured since putting one of the Torsen style carriers and all new bearings, no need for warranty. He came back $165 w/o warr. I said how bout 150 cash price... he said 150 + tax.. deal