The one ton has an additional leaf spring in the rear suspension giving it the added weight capacity. I tow a fifth wheel with mine and it performs beautifully... I definitely recommend the 5th wheel over regular tow behind. I had a tow behind before I traded up to 5th wheel and it is a dream to drive. My truck is SWD and it does all I need and then some. No need to enter the dually realm in my opinion, you just get more truck which costs more to own over the life of the truck (think about the additional tires, lower mpg, possibly more money at the toll booths and higher yearly registration cost increases...) Unless it is a working truck that really needs the heavier capacity in an everyday way, the SRW should do the trick. The only downside to 5th wheel vs. tow behind is losing some/much of the space available to you in the bed while towing, and the inconvenience of the hitch attachment brackets in the bed the rest of the time.