Buddy of mine has a 2011 Silverado with the 5.3, 6L80E, and a 76mm turbo. Right now just running on 6 pounds of boost until everything else is ready to go big. Truck JUST left our tuner yesterday, and my buddy broke something in the rear diff. (ring and pinion's been in bad shape, just a coincidence it went out), so what out there is the best replacement setup there is? Truck is daily driven, tows regularly, and street raced quite a bit!

 

If it were me, (and it will be me soon) I'd go with either 10.5 or 11.5 14-bolt with FF axle. Not only can you carry or pull more but with the FF alxe, in case of axle failure under hard exceleration, the tire wont rip off or axle slide out.. This has my vote.. I have seen quite a few axles break off the line at the drag strip.. Never ends well. Car/truck makes a hard left or right 90 right into the wall.. Not pretty.

 

That's kinda what i was thinking, a FF, like what I have in my 3/4 ton, but not aure how to drop from 8-lug to 6-lug.

 

I've been down the route twice of converting an 8-lug 10.5" 14-bolt from full-float to semi-float 6 or 5-lug. I will never do that again. The parts are incredibly expensive and you end up with something weak - you have to cut off the hubs and install custom ends, new brakes and backing plate, etc. They use a pressed steel ring to retain the bearing on the axle shaft like a Ford 9", but these rings are prone to walking with high side loads like drifting.

My advice, from personal experience, leave only two options:
1. Get a 9.5" non-floating 6-lug rear end. Available with 11" drums or discs. Load it with an aftermarket posi or locker. DO NOT leave a G80 in it. This axle housing will need to be from a GMT 800 or 900 truck as previous ones will be too narrow.
2. Install a 10.5" full-float rear - leave it 8-lug. Swap out the front rotors with the 8-lug versions from a 1500HD truck. (Never seen this done on a GMT900 truck before, might have to do spindles and brakes too.) And then of course new wheels.

 

Is it really that much of a hassle? I've looked over the years, and it's really hard to find the rear you're describing as #1. It's literally a direct swap though right? My rear discs and everything would bolt right up?

I know I've seen it before, but do you happen to know what vehicles were proper donors for the 9.5' rear? It would be going into a 2000 Silverado. It's really my last weak link.

Although, I don't know if a 10 bolt with a trutrac is really all that weak.

Thoughts?

Thanks!!

 

The 9.5 swap in a GMT800 has been covered several times. There are a few options.

The least expensive would be to get one from a 2005-2007 Classic 2WD SS, VHO, or Vortec MAX truck.

If you want other Idea's try this on for size... https://www.performancetrucks.net/fo...thread-467473/


For the GMT900, Look for one out of a Vortec MAX truck from 07-up.