[Mike Pearson]

That's some pretty poor fuel mileage. My Freightliner toterhome gets better towing mileage than that truck.

I have had 4 different dually pick up's all had diesel engines and all got about the same fuel mileage. 9-10 towing and 15-17 around town. My toter gets about 8-8.5 towing and 10 empty. Same trailer on all the trucks loaded 40 ft gooseneck 14K lbs.
That being said gas is cheaper per gallon than diesel fuel so that offsets the cost a bit. How much long distance towing do you do and what speed do you run when towing?