A friend of mine is buying a huge horse trailer, 17,500 unloaded and is planning to put his jeep and rhino in it as well as horses at seperate times. He already has nice 5.9 3500 probably 2006 model and a ford 6.0 3500. He is thinking about trading in the ford for a 6500 Kodiak with a sleved isuzu diesel not duramax. IMO he should modify the cummins and I think the trailer brakes will stop it. What do yall think? He says a friend that has a kodiak can get 11mpg probably at 22000 lbs and I told him it will get that with the cummins he has aspecially if modded. He should also get rid of that ford paper wieght... He was also thinking about the f550 but he was shocked when I told him they put the 6.7 cummins in dodges now, different trans tho. Any opinions???