Hey Guys,
I know there's a sticky on this topic but it doesn't seem to cover NNBS (maybe it does but it's 10 pages long and I didn't scan every post)

Just wanted to give some hope to someone looking to potentially doing this swap.
My truck is a 2011 Silverado 4wd/5.3 with GU6 and G80 options (10 bolt gov lock 3.42) with Drum brakes rear

I found 14 bolt from a junkyard truck. Factory half ton NNBS trucks could be optioned with the 9.5 14 bolt and that's what I found. They did NOT however come with a 3.42 so I had to opt for a 3.73
The swap could not have been any easier.
It required Zero fab work, zero extra parts, just basic tools.

I was able to reuse the driveshaft and u joint (no conversion joint needed, no shortening of the shaft)
Axle U bolts and "saddles" were reused
Soft Brake lines (4 corner ABS) and bracket were reused and connected right to the 14 bolt hardlines.
The 14 bolt has factory disc, I changed nothing with ABS or master cylinder and pedal feels just fine.

Wheels fit and have the same position in the wheel well because the axles are the same width.

All in all, it was literally like swapping in a replacement 10 bolt. Everything just fit and worked.
Thought I'd post this up for someone else to read in the future if they're researching a 14 bolt swap in a NNBS

p.s. I needed a 3.73 front diff to match and found a "CC8" 3.73 front diff to just bolt in .
The one I got came from a 4wd suburban but you can find them in trucks too...all the same

 

Interesting - I drive a 2010 NNBS Silverado 1500 2wd

Sounds like we need to find an axle that is:

• 07-13 Truck would fit fine - suburban/escalade/2500 I'm not 100% sure on the width
• Rear disc brakes
• Gearing option I'm not worried about - I have 4.88s not and run 37" tires

It seems like finding a factory 9.5 SF 14 bolt on a factory truck may be hard to do - might come on the Z71 model or a denali w/ the 6.2. I wonder which trucks have them? What model did you get your axle from?

 

The RPO option code is AXN. Typically found under the Vortec Max trucks so anything with a 6.0L or 6.2L. Stick with the 1500 truck for a bolt in application. Suburban, Escalade, and Avalanche will be a 5 link set up. Not sure the 2500's had them in the GMT900 Body style. By then, they were using the 10.5 floater axle or the 11.5 with a Diesel.

 

The 2500 suburban use leaf springs, but they are 8 lug, so they won't work on a 1500.

I believe the GMT800 and GMT900 2500 suburban axles are the same, at least until GM changed the lug nut pattern.

 

Careful now, they can be made to work. However it's far easier to get a bolt in unit.

 

Ah, that's correct. I had forgotten you can adapt them. Doh!

Do you have to replace the axle shafts? 🤔

 

Yes. 88-98 4x4 heavy 1500 or Light duty 2500 6 lug axles.