I've got a 96 F350 4x4 that I want to go bigger on tires to keep RPMs down. No, not huge off-road ones, but rather "D" or "E" radials. It has 265/75/16s on stock aluminum wheels. What is the largest size anyone has successfully run without hitting? I was thinking 285/75/16s should be fine, but would like to go bigger if I can.