14 bolt rear end swap?

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swathdiver

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Randy did a write up about the swap too. @randeez

Make sure the donor Escalade or Denali is RWD or it will have the same 8.6 we're trying to replace. Most of the ones for sale on ebay are NOT AXNs even though they say they are. When you check the VINs you discover that those are AWD and were not equipped that way. I tried telling them years ago and was ignored.

The only thing different that I've been able to detect is that the brake lines going to the differential from the body are different part numbers. Still, I know guys that did not replace them and have not had an issue. I bought them.

U-Joints are the same so it bolts right up, no need to shorten the driveshaft either.
 

OR VietVet

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Is there an assortment of ratios on the 2wd AXN axles? I would just stick with my 3.42 gears. Snappy enough and decent on fuel mileage.
 

CaptainAmerica1

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Most of the ones I’ve seen from the denalis are 3:42. Only reason I have t done the swap is that I’m saving for 3:73 and the axn swap. Haven’t done a rear end since I was 17 so I’m gonna pay someone else to set it up.
 

OR VietVet

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I have never tried to set up a set of gears. I think I could do it but I know it is an art and just like electrical diagnostic specialists, if you find a good gear guy/girl, they are always in demand.
 

randeez

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i believe all of the denali and escalade AXNs are 3.42s. there are allegedly some unicorn AXNs in avalanche/esky ext trucks that are 3.73/4.10s maybe ?

swap is direct, did mine in a couple hours at friends shop.

gear swap on them arent too bad. it was a little intimidating diy, but the process kind of ensures you get X set right before you move onto Y, before moving onto Z. if you cant get it within spec at any step you dont move on.

setting the pinion depth is no.1 - in my case the shims that came with the install kit i got put me too far or too close. so i used the smaller, but setting the backlash in spec resulted in poor tooth pattern. tried the larger, still couldnt get decent pattern when backlash was set to spec. ordered more shims, they took for fookin ever - i never checked the existing shim because i never took the bearing off the pinion gear but i ended up cutting the bearing off the old pinion to see what shim it had, and it was money. the 9.5(14 bolts in general) also has an adjuster on one side youre not messing with shims on each side of the caps, just one side.

now to preface all this - the few guys i talked to that knew gears told me : the first set up you should always,ALWAYS, set it up with whatever shims came out of it. because that is what it needs 9 times out of 10.

i didnt really document much cause i didnt really know what i was doing, wasnt sure if it would make it more than 5 miles, didnt want to put out bad info. i swapped 4.10s and a trutrac into mine....so far so good though!
 

OR VietVet

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i believe all of the denali and escalade AXNs are 3.42s. there are allegedly some unicorn AXNs in avalanche/esky ext trucks that are 3.73/4.10s maybe ?

swap is direct, did mine in a couple hours at friends shop.

gear swap on them arent too bad. it was a little intimidating diy, but the process kind of ensures you get X set right before you move onto Y, before moving onto Z. if you cant get it within spec at any step you dont move on.

setting the pinion depth is no.1 - in my case the shims that came with the install kit i got put me too far or too close. so i used the smaller, but setting the backlash in spec resulted in poor tooth pattern. tried the larger, still couldnt get decent pattern when backlash was set to spec. ordered more shims, they took for fookin ever - i never checked the existing shim because i never took the bearing off the pinion gear but i ended up cutting the bearing off the old pinion to see what shim it had, and it was money. the 9.5(14 bolts in general) also has an adjuster on one side youre not messing with shims on each side of the caps, just one side.

now to preface all this - the few guys i talked to that knew gears told me : the first set up you should always,ALWAYS, set it up with whatever shims came out of it. because that is what it needs 9 times out of 10.

i didnt really document much cause i didnt really know what i was doing, wasnt sure if it would make it more than 5 miles, didnt want to put out bad info. i swapped 4.10s and a trutrac into mine....so far so good though!
I did run a shop once where I had a gear specialist and until you said it, I forgot that he said the same thing. Always start your gear set ups with the same shims that were already in the axle, in the same position packs.
 

randeez

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I did run a shop once where I had a gear specialist and until you said it, I forgot that he said the same thing. Always start your gear set ups with the same shims that were already in the axle, in the same position packs.
yep. i figured since i was replacing carrier and all it wouldnt matter - cause no way the existing shims would be right (i was wrong).
i grabbed the "set-up" bearings from east coast gear supply, they are already bored out to slip on and off instead of ******* with the old ones and clearance them myself for $40 bux wasnt worth it. other reason was i dont have a press here (could have ran around and borrow friends but meh). to install bearings i just heated inner races up and the slid right on where ever (pinion and carrier)
the worse part is final installation of the pinion - you have the inner bearing with shim on the shaft already(its pressed on no problem there), it needs to go thru the housing, then crush sleeve, then the outer bearing (which has to be press fit on and bottomed out) or you cant put the yoke on and start the nut. and then you have to crush the sleeve to a specific ft lb while also checking the torque it takes to spin the yoke
 

OR VietVet

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My friend explained that the old/existing shims work, almost 99% of the time, because the same axle housing is used. If you have a different, used or new, housing, then the fun starts. He said, yes, every now and then there is enough difference in the gears and bearings that a different stack of shims is needed but the first response is always the original shim packs.
 

Dantheman1540

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Great call and I believe @Dantheman1540 has a write up about it, if I remember right.

Pretty much bolt it, possible U joint issue at-least when bolting to a GMT800. Any of the 99-14 rear brake setups with bolt right on, however you may have to change splash shields which required removing the axle shafts. Removing the shafts is cake with the axle on a table or stands.

4.10-4.56s and a trutrac would be my vote for a lifted truck.
 

Dantheman1540

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Here’s a link to my write up.

 

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