I don't see why you would have this. Maybe if you had a 1/2 ton truck and you wanted to pull a heavy trailer but then you probably shouldn't anyway because of brakes, motor, and transmission concerns. Harder to back up. More tires to deal with. Still need a load leveler. Very expensive. It seems like it would whip worse with this. The only pro I can think of would be it would wear your rear tires slightly less pulling a trailer. Or if you could use it between 2 trailers like a semi to pull the second trailer.