35" toyo RT's on on my silverado

Go underneath and look where the tires are rubbing. Do you need stronger springs and shocks to keep the weight from coming down or a higher lift or even smaller tires? You can do what is called "tubing" but that is a lot of metal fabrication and you also may be hitting on the frame. You may need to add offsets on the tire rims to push the tire out. Is it the front or rear that rubs? Front, change tires. Rear? stiffer suspension or add more lift or do the above. If the tires are not rubbing the outside under fender, find out how much you can go out if it is rubbing the inside near the frame. Remember some tire shops will sell you what you ask for, others will know and tell you if what you ask for will work or not.