You can fit 315 75 16's BFG's on a stock 2500,although they will rub on the link bars at full turns,therefore I shortend my steering with stop bolts on the spindles. They work great i'm on my second set, I got over 40,000 on the first. The other nice thing is a 2. 5" coil to level the truck,skyjacker makes it ,around $200 .