2014-19 Axle Swap on a 2007-13 Silverado?

Matt2013LT · June 28, 2023

I presently have a 2013 Silverado LT CCSB 2wd 5.3 With a 6L80. It has a 10 Bolt rear end (GU4) with the sad 3.08 Axle ratio. What's really bad is that I am currently running 35x12.50R20 Nitto Trail Grapplers on 20 inch 2020 Silverado RST wheels with that very high gear ratio. 6th gear is basically unused at this point even doing 60 on a hwy. From what I understand, the 12 Bolt rear ends from the 2014-19 Silverado's are stronger than the ones on 2007-13s! Well a nearby junkman had a 2015 Silverado 5.3 Double Cab + 6 3/4 Bed. It was a 2wd WT Trim level, White, very bare bones pickup, that had also been in a front end collision. The scrapyard owner had the axle for a low price, so I hopped on it. I currently have the axle in the process of tearing it down. My goal with the axle is to clean it up, get it powder coated red to match the truck, and swap a 4.10 axle ratio into the 2015 Silverado 12 Bolt rear axle. From what I understand the 12 Bolt can handle more power, weight, and is stronger than the 10 bolt. And the 12 Bolt I picked has disc brakes because it's from the 2015 Model Year. For anyone that is still reading & has knowledge about this, is there any big modification I have to do? The 10 Bolt & 12 Bolt Axles both look as if the shock mounts & where the leaf springs rest, are in the same positions for mounting! I heard I might have to swap brake master cylinders if I do a disc brake conversion because the 2013 Axle has drums, while the 2015 Axle has discs. Any advice anyone can give me would be appreciated! Thank you.

CamGTP · June 28, 2023

My question would be about the ABS and stabilitrak system. Are those going to plug in and work with the older computer systems. If the rear speed sensor pick ups are a different tooth count, you'll get problems there.

Matt2013LT · June 28, 2023

38 minutes ago, CamGTP said:

My question would be about the ABS and stabilitrak system. Are those going to plug in and work with the older computer systems. If the rear speed sensor pick ups are a different tooth count, you'll get problems there.

You bring up a great point! I did not think about the tooth count being different! Will definitely look into that! I did get the wiring for the ABS from the 2015 Donor truck, so I suppose I'll have to see if they match or if I need to retrofit some things! Thank you for the input.

tarmitage92 · July 6

Did you ever end up figuring out the full answer here about possibly using the axle from the newer truck?

swathdiver · August 7

Anything can be done with enough money. A great upgrade for the GMT900 pickups is the 9.5" 14-bolt semi-floater. These axles were found behind RWD and 4WD 6.0 and 6.2 1500s, not AWD Denalis.

With the same 1355 u-joints, they swap right over for most applications. They come with disc brakes.

They are basically plug and play.

Edited August 7 by swathdiver