Tractor First, Right?

For primarily an offroad truck, I would want a heavier duty truck. Thicker frame, heavier steer axle, full lockers like @Lepton1 mentioned, 46k rears. A heavy 3. Standard issue truck in Canada and Michigan. Thats where you start looking.

Heavy trucks like a hard life. Inframes should have documents otherwise it never happened. When looking at a truck, take it to Speedco for an oil analysis.

 

Avoid anything Volvo.

 

Get it dyno'd no matter what you are looking at. A couple hundred bucks now to walk away could save you tons.

Going to florida and back you should just get someone else to take it. Be way cheaper in the long haul. WAY. Figure it's a buck a mile just to run your tractor/trailer, you can have it done, fully insured for about that (people are stupid, they always low bid it), let them do it and bring it to you.

 

He means a heavy spec 3 axle tractor. 20k front axle instead of normal 12k and 46k tandems instead of 34k. Also called a "Michigan Special".

 

I do up to 9 axle lowbed work with a 12k front end. I would be more concerned with gearing and rear ends

 

13 or 18 speed. Pulling heavy and up hills the rpm spread is too far apart. On my run, my 13 speed tops the hill at 10-15 mph faster than the 10 speed I ran and that is because you can stay in the power longer.

I have run with cats, Cummins, Detroit and paccar motors when I drove a cat and they all get the job done. I can tell you that my Detroit does not pull like a cat but it doesn't drink like one either. The cat also was a c15 vs a 12.7 and had an extra 100 horsepower.

 

Which Cummings? Like/hate? How did it compare? Thanks