The only difference between an F250 and a F350 is a two inch spacer block, a helper spring, and recommended air pressure. Drive train brakes etc. are the same. Air pressure should be pumped up to max on the tire sidewall. SRW will do fine. If you are full timing then dualie should be seriously considered. If just weekend/vacation the disadvantages of a dualie might not out way the advantages. I have a F250 that I pull a 38 ft Montana with. SRW. I added air bags and a rear stabilizer bar. Good shocks are a must also. I use Blistein. Tires are goodyear wranglers run at 80 psi. The main thing is do not over drive your capabilities. I do think if you go with a dualie an air king pin is a must to absorb the extra shock so the helper spring.