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)

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5StarCustmSolutns
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Well, 340+mi round trip to learn: The sales staff at Bessler Auto Parts will sell you absolutely anything you can articulate in an understandable manner.. Also learned: Whether Bessler actually, physically has said item or not, and how that may or may not inconvenience you is completely irrelevant to the sales and management(or lack there of) staff at Bessler. And as a bonus learned: Bessler actually, physically has NONE (ZERO) of the dozen or so 14 bolt 9.5" rear ends they list as available for sale on car-part.com....:oops:

That's approx 480mi in two days with ZERO 14 bolt sightings. Fool me twice....

I feel like this thread is turning more towards a daytime soap than something a person might gleen some helpful info from someday in the future? May ask admin to change thread title to: As the Salvage Yard Turns (pretty sure that's my first ever "if you're under 35 you may not get it" humor attempt)

I need to ask a really beginner question to be this far into this:

Is there such a thing as a 10-bolt GM rear axle assembly that came with a 9.5" ring gear, w/spring perches, that bolts up to a GMT920, 930, or 940??

EDIT** fool me twice is fool me twice but Corey the doucher that sold me the axle Thur assured me they had multiple candidates onsite(bc you can't just call there yourself for some Fn reason) and he didn't email my receipt on Thurs like he said he would.....by time I checked they were closed. I called soon as they opened yesterday morning and Corey was off but Casey emailed me receipt immediately and I bolted because my ride was sitting outside waiting on me.....I didn't even think to check VIN until I got home. VIN comes up as 2012, receipt says axle from 2008.....I could type 5000 words and not cover what all happened yesterday, but I don't do drama. That $hit is in rearview mirror. Trusted mom and pop parts dude Thurs, and Giant mega salvage place Fri and they showed how much they have in common....neither pays any attention to detail whatsoever, nor do they care about anything but themselves and more importantly....money

another really entry level question:

Is there any GMT900 Truck axle that I can weld spring perches and shock shackles accordingly on??





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Foggy

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Not that I know of avail... When I looked for my rear diff I specifically researched the
exact model it came from... Because the salvage guys just know "it fits"
Don't care if it's the 8.6" rear or the actual 9.5" that I really want...
Anyway, I haven't installed mine yet... I do own all the new parts to make my
8.6" stock awd differential "strong".. But those parts are still hanging in a box... still..
So at some point I;ll either use the $700 worth of 8.6" parts to beef up my stock rear or
install my new to me 9.5" 14 bolt
 
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Not that I know of avail... When I looked for my rear diff I specifically researched the
exact model it came from... Because the salvage guys just know "it fits"
Don't care if it's the 8.6" rear or the actual 9.5" that I really want...
Anyway, I haven't installed mine yet... I do own all the new parts to make my
8.6" stock awd differential "strong".. But those parts are still hanging in a box... still..
So at some point I;ll either use the $700 worth of 8.6" parts to beef up my stock rear or
install my new to me 9.5" 14 bolt

I was pretty sure it didn't exist, but two days in a row at two diff yards in two diff states these places were trying tell me that the 10 bolt I was looking at had a 9.5" ring gear in it... Both were like "but it's a GU6 9.5, what does the number of bolts on cover have to do with that?" After about 30min and 2 different fake managers calling me to ask what my VIN was, and telling me that their system showed that axle was a direct bolt up, I looked at my buddy and said "I feel like I'm taking crazy pills! I mean wtf is going on here? Are you hungry yet? If you'll take me away from here immediately I'll buy your lunch" and we rolled out...

I read a couple days ago that, either the 9.5 or 9.25 IFS, was 67% stronger than what's inside the 10 bolt front rear? Also found a graph using a cubical equation that was figuring axle strength in based on # of splines. Not sure how solid those two articles are but there could be some validity....

edit: Heres cubical equation piece:


I've thought all day about just beefing up 8.6... But I feel like that would be letting them win at this point? Plus for what I do it just makes more sense to go 9.5... It is nice that you have the option though :)
 

swathdiver

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LKQ shows you the donor vehicle and VIN and photo of plate on door. They have plenty improperly listed so you have to dig.

The VIN on that 2008 is from a 2012 AWD as you mentioned and of course it will have an 8.6 axle.

The 6.2 GMC 1500 Pickups in our generation are also equipped with the 9.5" semi-floater but of course are set up for leaf springs. They come with 3.42 or 3.73 gears. The 2007-2009 6.0 Vortec Max 1500s also ran this same axle and some of those might have 4.10 gears (2007-2008). All of them will show RPO AXN on their build sheet. VIN number for the engines are either 2 or Y. Extended Cab or Crew Cab only. Unfortunately, they are much more expensive, around $1K and there are 3 on LKQ right now, 2 in Houston and 1 in New Mexico.

Savannah, Georgia and Trafford and Montgomery, Alabama are the closest ones I see to West Virginia for SUV axles that will bolt right up to yours.
 
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LKQ shows you the donor vehicle and VIN and photo of plate on door. They have plenty improperly listed so you have to dig.

The VIN on that 2008 is from a 2012 AWD as you mentioned and of course it will have an 8.6 axle.

The 6.2 GMC 1500 Pickups in our generation are also equipped with the 9.5" semi-floater but of course are set up for leaf springs. They come with 3.42 or 3.73 gears. The 2007-2009 6.0 Vortec Max 1500s also ran this same axle and some of those might have 4.10 gears (2007-2008). All of them will show RPO AXN on their build sheet. VIN number for the engines are either 2 or Y


Thanks for the info on the leaf spring options! At the end of this thread, assuming I make it there, I'd like to put together a master list of all direct bolt up axle options for '07-'14 GM full-size SUV/SUT. I think it would shorten the learning curve for anyone who wants to do this. A little surprised I haven't come across one yet?

I haven't been able to find an RPO list with AXN on it? Is it an actual RPO code or an Option code or Axle ID Stamp maybe? Just curious what it says/distinguishes? I thought it signified a 14 bolt 9.5 rear-end out of 2wd? but I also first saw the inside of a diff 3wks ago lol

This all the AX_ that are on the best list I have? It "says" Master List at the top but who knows? 188 pages

AX0 855 P PAR R PARTITION TUBULAR FRAME, DRIVER 990910 E B E A
AX1 856 P PAR R PARTITION MESH TYPE, W/WINDOW 980901 E 8 E A
AX2 857 P SPK M KEY COMMON, VEHICULAR UNIQUE 840417 E E E A
AX3 858 P LCE R LOCK CONTROL, ENTRY REMOTE ENTRY - DEALER ACTIVATED 11010 E Z E A
AX4 859 P RESTRAINT CONVERSION SEAT, MAN, EUROPEAN 900419 E E E A
AX5 860 P PAR R PARTITION MESH, DRIVER 980421 E 0 E A
AX6 861 P PAR R PARTITION SOLID TYPE 980423 E 0 E A
AX7 862 P PAR R PARTITION EXPANDED METAL, W/CTR SLIDING DOOR 970715 E 1 E A
AX8 863 P PAR R PARTITION MESH, DRIVER & PASS 980421 E 0 E A
AX9 864 P PAR R PARTITION SOLID TYPE, W/WINDOW 980624 E 0 E A
AXP 844 P VIN IDENT POSITION, MULTI-PURPOSE VEHICLE 890110 P T T A
AXQ 845 P VIN IDENT POSITION, BUS 890110 P T T A
AXR 846 C VIN IDENT EXPORT SPECIAL 951006 E T T A
AXV 850 P GBS R WINDOW SIDE BODY SLIDING

edit: check that I finally found proof RPO code AXN exists, in shop manual for 2011 3500 ;)
REAR AXLE
1000 Series without RPO AXN (8.6") .............................................................................................................................................. 2.03 liters (2.15 quarts)
1000 Series with RPO AXN (9.5"LD) ................................................................................................................................................ 2.6 liters (2.75 quarts)
2000 Series (9.5"HD)


Earlier today I closed some(like 12) tabs and started a fresh search for any and all things related to this, and there were only 2 links in the first 4 pages that I hadn't already visited, maybe 10 links through first 8 pages...
Today was 23rd straight day I've been at this. At first it was like cramming for a test, and I was a little hesitant to ask questions until I had a better grasp of what I was asking about. Felt a lot like this o_O
I really appreciate all the guidance and sharing of knowledge. Call it karma, call it the golden rule, call it whatever you want; it's fact of life....when it goes around....it comes back around.

Proverbs 1:2-7
 
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swathdiver

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Yeah, that shop manual is in error too, the 8.6 is a 10-bolt axle and gets no special RPO code and certainly not AXN.

Myself and others have posted which trucks came with them from time to time over the years, buried in posts about gear changes, axles, etc.

The world would be a better place if each man and his family would hide the book of Proverbs in his heart!
 
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HA! It's almost like they don't want you working on your own late model vehicles?

I've got a master list of possible donor vehicles started now; and when/if I survive this battle along with the battle I'm in remodeling our kitchen. I'll go back, find others and post consolidated list
 
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So I think I've finally found the description for the ever elusive RPO Code: AXN

[ this is straight from a manager for GM. If anyone disagrees or knows different please educate us all ]


So it most definitely distinguishes the larger housing needed to fit the larger 9.5" ring gear and carrier. The 6 lug (let's call it a 2/3rd ton) 1000 series Rear Axle that uses the 9.5" ring gear. However, it distinguishes it in a way I would'nt have ever guessed.

RPO AXN = 2.75qt capacity/rear differential


8.6" 1000 series = 2.15qt (w/o RPO AXN)

* 9.5" 1000 series = 2.75qt (RPO AXN) - 6 lug

* 9.5" 2000 series = 2.75qt also (no RPO listed) - 8 lug

* 10.5" 2000 series = 2.75qt (RPO LY6) - 8 lug

* 11.5" 2000 series = 3.17qt (RPO LMM) - 8 lug


* = 14 bolt housing
 
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