Wheel / Tire Question

tightline07 · April 27, 2011

I have a 2007 GMC CC Z71 with factory 20's. Going to put a 2" leveling kit on it and thinking about putting the XD HOSS in a 22X9.5 with a +30 offset. Not sure what tire i can run or if i can run that wheel and tire combo without more lift. I have never dealt with anything bigger than a 20. Or should i just go with the 20X9 with a +30 offset and what tire size? Any advice would be appreciated.

mhenshaw · April 27, 2011

22x9.5 with +30 would be 1" farther in than the stock 20x8.5 wheels so it might rub the suspension.

20x9 with +18 offset and 305/50r20 fit with a leveling kit.

tightline07 · April 29, 2011

22x9.5 with +30 would be 1" farther in than the stock 20x8.5 wheels so it might rub the suspension.

20x9 with +18 offset and 305/50r20 fit with a leveling kit.

Correct me if im wrong but wouldnt it just be 1/2" farther in rather than an inch? Because you would get half an inch each way instead of just the inside. From what i have gathered the factory offset on my 20's are +31. So would a 22X9.5 with a +30 sit about the same as the factory wheels? I just want it to fit without rubbing and not stick out past the fender. i want it to be flush. thanks again

Matt_ · April 29, 2011

Correct me if im wrong but wouldnt it just be 1/2" farther in rather than an inch?

That is correct.

Offsets can be very confusing. I prefer to convert it to Backspace which is MUCH more intuitive.

For instance, 9.5" wide with +30mm offset equates to (rounded) 6.5" backspace. So the outer edge of the wheel sits out 3" from the hub (9.5-6.5=3.0). Whereas 8.5" wide with +30mm offset equates to (rounded) 6.0" backspace. So the outer edge of the wheel sits out 2.5" from the hub (8.5-6.0=2.5). Thus, the 9.5" wide wheel will stick out 1/2" further. It will also sit 1/2" further under the truck as well (6.5" BS compared to 6.0" BS).

Attached is my "go to" chart for converting.

tightline07 · April 29, 2011

With that being said would what im wantin to do work out ok or will it have clearance issues and stick out to far? Like i said im fairly new to the whole offset/backspace stuff.

Matt_ · April 29, 2011

With a 305/50/20 you should be alright with the fenders.

The only thing im not 100% sure on is the 6.5" backspace. I believe you'll be OK there as well since you won't be running a 33" or taller tire, otherwise you may rub the sway bar some.

tightline07 · April 29, 2011

With a 305/50/20 you should be alright with the fenders.

I was hopin to put a 22 and an all-terrain. Am I gonna be able to put a decent looking tire that will have some sidewall to it. I dont want rubber bands. I'm really at a loss on this one.

Matt_ · April 29, 2011

Didnt even notice that you wrote 22, not 20.

With a leveling kit, NO, you're not going to get much sidewall at all with 22s.

With 20s you can get quite a few A/T tires. With 22s, you're going to be stuck with street/performance tires in the sizes that'll fit without a 6" + lift.

Look at my Sierra pictures when i had the black Novakanes. Those are 305/50/20s. You won't be able to fit a taller tire than that... and with 22s, you'll have an inch less of sidewall!!

tightline07 · April 29, 2011

man that trucks looks awesome... what exactly did you have done to it so ill know what to do and did you have any rubbing issues or anything at all?

Matt_ · April 29, 2011

3" body lift, 305/50/20s, 20x9 with 0mm offset (5.0" backspace). Slight rub on mud flap... didn't make any noise, but i saw the rub mark. (if it make noise, it would have been cut off instantly, i HATE rub noise). With 9" wide and 5.5" backspace (+18mm) they would probably fit good with a 2" leveling kit.