[Bowtiepower00]

I've been stockpiling parts for my 07 Silverado Classic C1500 (2WD) for awhile now, got a 7" RCD lift, 17x9 wheels, and 33x12.5 tires holed up in the garage, going to throw the lift on in the coming month or two.

I'm going to regear to 4.56, and throw an aftermarket posi or locker in when I install the lift, and wanted to see if any of you have any experience with either the Eaton or Detroit in a newer truck w/ the 8.6 (newer 8.5) rearend.

The truck is my DD, and will see occasional towing as well as light desert trail running.

I've had a Detroit in a DD before, but the truck was a 80 K20 with a 4 speed, apples to oranges there.

I am familar with the characteristics of a Detroit on the street, and it never bothered me in my K20. Increased tire wear is not a concern, nor are the street manners.

I am, however worried about the durability of the 8.6 with a Detroit. I would consider adding aftermarket axleshafts down the road, but am not interested in swapping the entire rear. I have my doubts as to the durability of the Eaton (particularly the clutch disks) as well as the amount of spin it is going to allow if I get into some deeper sand, etc., or other situations where one wheel is wanting to spin.

Are Carbon Fiber disks available as an upgrade for the Eaton in this application? I've seen them listed for the 9.5", for example, but never specifically for the 8.5/8.6. I don't mind replacing the disks every few years, but I don't want to be doing it every season.

Anyone out there with any real world experience with either Differential in a similar application? A drop-in locker is not an option, I have the factory G80 gov-bomb (which lasted approx 20K from the factory.)

The truck is not going to be hammered on, or wheeled hard, I just want a good looking mall-crawler with some offroad ability should I need it.

Not looking for any "why are you lifting a 2wd, etc." comments either, I have little to nothing in the parts I have gathered, the truck is paid for, upgrading to a 4x4 is not an option, and I live in AZ, the truck is not going to see snow and ice. I do not have the time or money to build a dedicated trail rig. I also understand the front end and rearend are not bulletproof, and I will keep this in mind if/ when I ever get offroad. I just want to be able to take an occasional Forest Service road without scraping or getting stuck. This is not my first rodeo, I would just like some real world experience before plunking down my money on a posi or locker for this application.

Thanks...

[JKLNHYD]

I've punished some pretty gnarly offroad vehicles with both products even though the application may be slightly different. But overall, both are very reputable units and will handle a fair amount of abuse. In fact, you have already noted the only thing I would have mentioned: replacing the axleshafts. But be aware, do your research before buying the locker as the spline count on the stock shafts may differ from the stronger shafts you would buy down the road. In the end, the locker will most likely be the strongest part of the rear end...Good luck!

[Bowtiepower00]

Thanks for the reply.

Did some research at a couple of forums that reinforced what I thought I'd read a few years ago.

The Eaton Posi, even with increased preload, and CF springs, wears quickly and doesn't work very well in situations where you get one tire really wanting to spin.

The full Detroit, in the 10 bolt, allows enough banging and clanking to snap axleshafts and even driveshafts in some situations. I know in the Toyotas a snapped axleshaft frequently takes the Detroit with it, and I don't really want to be worrying about axleshaft issues if I can avoid them.

The Detroit would be my choice if I had a stronger rear, but since I'm stuck with the 10 bolt, and don't want to swap to the 9.5" for cost purposes, It looks like I'm going to go with the True-trac.

The True-trac appears to have the best balance of durability and amount of lockup for what I'm doing. I was hesitant to go this route at first due to the amount of failures I've read about, but pretty much all of them were in 7.5" 10 bolts and 12 bolts running on the strip with sticky tires.

Anyone run a true-trac in a 8.5 or 8.6 with mild offroading? I saw a few failures, but all of them were on guys really beating on their trucks, in situations where I wouldn't want a 10 bolt anyway. The price is right, too.