I have a 2004 2500HD w/6" lift and 3.73. My final drive ratio is now somewhere around 3.22. If I bump up to 4.11, I get a final of around 3.62, as close to stock as one can get with what is available. GM wants $900 plus just for the rear ring & pinion which is about 3 times the cost of all the 4.11s I've found out there. If go outside of GM, will I cost myself the entire drivetrain warranty? Obviously, I would go back to have axle work performed by the outside shop, but if I blip the box for an axle ratio other than what it came with, I'll be busted. Just curious.

The stealers have been instructed to not even troubleshoot driveability problems if the stock size tires and wheels are not on the vehicle.


Some will still work with you, some won't, and you want to change the differential ratios?


I'd suggest having a discussion with your local SM for his input on the idea. That doesn't guarantee no warranty problems down the road, but if he says no warranty if you change, well...http://www.dieselplace.com/forum/smileys/Dead.gif

I will, again. I pretty much firmed up it wasn't gonna be a problem if I lifted it before I ever did it, actually, before I bought it. They said if I brought it back to them, they'd take care of me. Guess we'll see where they stand on this. Thanks.

Confirmed it today with the dealer. They won't let an outside shop do the work, but they will let me provide the parts (huge savings!http://www.dieselplace.com/forum/smileys/Big Smile.gif) and they are only about $60.00 more for the labor and my warranty will be intact! Should be able to get the regear (front AND rear) done for about $1050+/-. Pretty good considering Dealer wants $950 just for the rear ring & pinion. Hope this may help someone else too.