Just bought an 05 GMC 1500HD 4x4 Crew with QS and love it! I am certain you guys have dealt with this in the past, but wanted to know what is the talles rim/tire combo I can put on this truck without a lift. Currently everything single thing is stock, so the rims are 16's and the tires are 245 75 16's.
Also, have read some stuff on PCM tuning and wanted to know which way to go. Send it off or buy a remixed PCM or buy a programmer and do my own.
Help would be greatly appreciated.
Thanks

Without adding a lift kit the largest tires you put on the truck are 265's. You can reprogram the computer using the hypertech but I have learned that the dealer will now do that for you. When I changed the tires back in 04 they wouldn't but you can try them. It might save you some bucks verses buying the hyper tech. Also, I have wanted to buy a lift kit for my quad but I don't know of any one that makes one.

If you don't mind trimming plastic, you can fit 285's. If you also crank the torsion bars, you can fit 305's (33 inches tall). If you are changing rims, and you do not want to rub, then keep a 5 to 5.25 inch backspacing. Many of the rims are 4.5 inches, which many lift kits require, and they tend to rub more than rims with larger backspacing.

Gaustin12, Pro-Comp makes a 6" bracket lift kit that is compatible with the quadrasteer. I put it on my truck and it is very well made and I would recommend it. I am running 35's, but I think that I could put 37's on if I use the right wheel.

Gary

so, if I wanted to add some 20" by 10" rims, I will need to keep the profile of the tire down to 265. Sound right? Anybody weigh in on the pcm controller?
With gas prices goin' north, I may wait on the larger tires and focus on the better gas performance. Right now, it looks like I'm getting around 11 MPG in town and about 15 on the road.

one last thing, did I tell everybody I LOVE THIS TRUCK! There has got to be some way for GM to start making the QS again. I could have bought a newer truck, but I wanted the QS and now that I have it, I want it even more.

Belated welcome quadco.

Don't waste the money on a hand-held. For the money, a Westers or Nelson tuning is a better alternative as far as value. Currently I'm using the Westers and have no complaints.

Do a little homework on the type tires for your needs. Criteria like rolling resistance for one, can attribute to better mpg.

I'd be surprised if the General would be the maker with QS. The 2 I've heard if resurrected would be Nissan or Toyota.