I've been running 33's (285/75/16) on the factory "cyclone" wheels for almost 2 years now. No rubbing at all. Z71 springs in the back (my 'Burb is an LT) and eBay lift keys up front. Runs great, handles well. I'm a pretty mild off roader (you don't take a Suburban onto gnarly trails anyway!) and this setup has worked very well for me. I'm pretty happy overall, my total investment in my lift is under $600 and that includes the $150 I had to pay to a shop to bust the factory T-bar keys loose (they were rusted in place - thanks to my truck spending it's first 8 years in Wisconsin!)