I increased the lift on my 2002 Tahoe LT 4x4 from 4.5 to 6" and swapped the 33" Nitto Ridge Grapplers with 35s. It's a monster now!

UPDATE: I guess the lift settled after a few days or something–it sounds weird, but when I went back to the shop to trim the bumper, wheel was no longer rubbing the bumper. We just had to trim some more of the inner wheel well liner and that was all–it barely rubs at all now! (just a tiny bit at full turn in reverse)