1/2 ton?3/4?1ton?
kinda hard to give you a size without more info. but for tire i am running nitto terra grapplers. seem really good i have about 5000k on them and like them. d rated load and still fairly smooth and quite on the highway. reasonable pricing to for all 4 mounted balanced 285/70 18s was 1200.00 bucks with taxes.
get a 35x12.50 dick cepek fc2, my buddies running them on his welding truck and had 70k on them and they have about 25% left. to run 37's you'll need fender cut outs