1500 to 3500 rear axle swap 08 Sierra crew cab

[intelified]

Haven't seen my year group covered with this swap. 08-13 body style.

Need some help please.

I have an 08 1500 crew SLT 4x4 and need a rear axle that will handle high HP and torque.

Would this be possible to swap in same body style HD rear axle as I would like to retain all electronics, posi and traction control. (I know the HD is 3" wider and 8lug... That's not a concern) also, gear ratio is not a concern.(it has to be changed anyways)

Any and all help would be greatly appreciated.

Thank you.

[2018GMC]

Haven't seen my year group covered with this swap. 08-13 body style.

Need some help please.

I have an 08 1500 crew SLT 4x4 and need a rear axle that will handle high HP and torque.

Would this be possible to swap in same body style HD rear axle as I would like to retain all electronics, posi and traction control. (I know the HD is 3" wider and 8lug... That's not a concern) also, gear ratio is not a concern.(it has to be changed anyways)

Any and all help would be greatly appreciated.

Thank you.

 

Look for a 2007.5 - 2013 GMT900 2wd Denali, Escalade, or 4x4 (Sierra / Silverado) with max tow package and 6.2l. These 1500’s had the larger 9.76” rear axle which could handle 403hp / 413 tq and towing 10k Per GM.

 

VortecMAX trucks with the 6.0 also got the larger rear axle.

 

the AWD Sierra Denali and Yukon Denali with 6.2 got the smaller rear axle so disregard those.

[intelified]

21 hours ago, 2009GMC said:

 

Look for a 2007.5 - 2013 GMT900 2wd Denali, Escalade, or 4x4 (Sierra / Silverado) with max tow package and 6.2l. These 1500’s had the larger 9.76” rear axle which could handle 403hp / 413 tq and towing 10k Per GM.

 

VortecMAX trucks with the 6.0 also got the larger rear axle.

 

the AWD Sierra Denali and Yukon Denali with 6.2 got the smaller rear axle so disregard those.

Thank you. Would you happen to know how many bolts on that 9.76" rear axle? 

Also, what about the humvee H2 rear axle? Wasn't that bigger and have all the electronics? 

[Mike GMC]

I wonder how well a 14+ semi floating 12 bolt would work.  With the 9.5" ring gear and 33 spine axles it should be a big upgrade in strength from the 10 bolt.

[intheburbs]

The H2 got the 10.5" full floater 14-bolt from AA, same as my 2500 Burb. 

[intelified]

5 hours ago, Mike GMC said:

I wonder how well a 14+ semi floating 12 bolt would work.  With the 9.5" ring gear and 33 spine axles it should be a big upgrade in strength from the 10 bolt.

Thanks, what is that rear off of? 

Basically need a bigger rear axle that retains the factory electronics and that can also be upgraded to handle very high hp and torque 

[Mike GMC]

It from the 14+ Silverado/Sierra 1500 trucks.  Same lug pattern and the older 1/2 ton, good brakes.  Not sure if the width is the same or if the ABS would be the same.  I don't know of any other electrical besides the ABS sensors.  The one bad thing about that axle is limited gear ratio choices and limited posii/locker choices.  There just doesn't seem to be much aftermarket support for it yet.  If you want 3.08, 3.23, 3.42 or 3.73 it may work for you.

[michigan2500hd]

 
Look for a 2007.5 - 2013 GMT900 2wd Denali, Escalade, or 4x4 (Sierra / Silverado) with max tow package and 6.2l. These 1500’s had the larger 9.76” rear axle which could handle 403hp / 413 tq and towing 10k Per GM.
 
VortecMAX trucks with the 6.0 also got the larger rear axle.
 
the AWD Sierra Denali and Yukon Denali with 6.2 got the smaller rear axle so disregard those.

I was under the impression that the axle from max tow 2007-13 was a 9.5". The 9.76 came out with the max tow 2014 and up 1500. I could be wrong but that's how I've seen it referred to as.

Sent from my SM-N950U using Tapatalk

[intelified]

1 hour ago, Mike GMC said:

It from the 14+ Silverado/Sierra 1500 trucks.  Same lug pattern and the older 1/2 ton, good brakes.  Not sure if the width is the same or if the ABS would be the same.  I don't know of any other electrical besides the ABS sensors.  The one bad thing about that axle is limited gear ratio choices and limited posii/locker choices.  There just doesn't seem to be much aftermarket support for it yet.  If you want 3.08, 3.23, 3.42 or 3.73 it may work for you.

OK, thanks. I'll try and research that.  I'm running 4.56 due to weight and wheel size

[intelified]

8 hours ago, Mike GMC said:

I wonder how well a 14+ semi floating 12 bolt would work.  With the 9.5" ring gear and 33 spine axles it should be a big upgrade in strength from the 10 bolt.

Which axle would that be? I'm putting down over 700lbs of torque...

[Mike GMC]

700 ft-lbs?  Nice!  With that much, you might want to stick to the 14 bolt, or even look into something custom from Currie or Strange.  I would guess the new GM 12 bolt is good for 500 to 600 ft-lbs all day long, but your well over that.  Besides, with a 4.56 gear, the pinion gear is tiny, the bigger the ring gear, the bigger the pinion gear.

[2018GMC]

I was under the impression that the axle from max tow 2007-13 was a 9.5". The 9.76 came out with the max tow 2014 and up 1500. I could be wrong but that's how I've seen it referred to as.

 

Sent from my SM-N950U using Tapatalk

 

 

Michigan2500hd. You are correct. GMT900 gen has 9.5” 14 bolt rear for max tow. K2XX gen has 12 bolt 9.76” rear for max tow.

[2018GMC]

Thank you. Would you happen to know how many bolts on that 9.76" rear axle? 
Also, what about the humvee H2 rear axle? Wasn't that bigger and have all the electronics? 

GMT900 gen has 9.5” 14 bolt rear for max tow. K2XX gen has 12 bolt 9.76” rear for max tow.

Guessing the Hummer had the same 14 bolt semi float rear. Anyone guess if the electronics will play together. Take pics of your connections on your truck before you go junkyard hunting and see it they match at all if you find a suitable axle.

[2018GMC]

FYI - GMT400 trucks also had a 14 bolt semi float 6 lug rear. I bet abs wouldn’t work but the axle is same as ld2500 but with 6 lugs and semi float. Drum brakes though. F44 code in glove box.

 

Also look into the gmt800 1500hd trucks which had the 2500 semi flat rear axle but 8 lug.