I don't know that anyone is fitting 33x12.5 (approx. 315 width) tires with no lift and no level. That's a pretty wide tire for a stock truck, to not rub when compressed at full lock. I'm pretty sure it won't rub when just driving down the street, but that's not exactly the definition of "doesn't rub." A 33x11.5 (285 width) should fit any new, stock, full-size 4x4 on OE wheels, since current models offer 33's as a factory option (usually 275/60r20). The K2 generation GM 1500's were a snug fit for a 285/70r17 or 285/65r18 without a lift or level, even on stock wheels. Allegedly they will fit without rubbing on stock wheels, but there's enough conflicting information that I wouldn't count on it - tire width was the issue, not height.