Greetings All. I couldn't find this topic on any of the forums, so this looked like the logical place to start. I'll try to keep this short. I run a RAM with a 6.4 pulling a 36' toy hauler averaging 6 to 8 MPG. I had the opportunity to visit with a transporter running a 1 Ton RAM with a Cummings. The topic of fuel mileage came up, and he stated even with the diesel he didn't get but 8 to 10 MPG pulling Travel Trailer Toy Haulers like mine. It occurred to me that a truck topper might improve the aerodynamics of my set up. So my question is; who pulls a TT Toy Hauler with a Truck Topper, and have you calculated your average mileage with and without it? Thanks All.