I've ran 35x12.5's with a 2.5" leveling kit on my truck since I've owned it. The only rub i have is on the trac/control arms at full lock. But it was with stock wheels. I was told that with a leveling kit you can't going anything bigger than a 33" without it becoming an issue. IMO I wouldn't go any bigger than 33's if you're just doing the level lift with the wheels you want. If you look around youll find threads and arguments about what will and won't fit. I'd say your best bet is when you go to buy the wheels and tires make sure to ask what is the best wheel/tire/lift combo and they should be able to help for sure. Hope this helps and good luck.

 

Stock tires (265/70R17) are roughly 31.6 inches, and you could go as large as a 305/65R20 and it shouldn't rub at full lock. The 305/65R20 is a 35 inch tire with a 12 inch width, and with the 3 inch leveling kit you "should" be able to run 37's without with minor rubbing at full lock.

Use this tool for figuring out what you need:

Tire Dimensions Made Simple - Discount Tire






Kris