i was wondering if anyone might know what mpg i might expect pulling a 3000# 21' travel trailer with my truck: '03 dodge 1/2 ton 4x4 crew cab with the 287 4.7L 5spd auto with 3.92 gears. according to trailerlife.com my towing cap is 7250#, my city mpg is normally around 13, on the hwy i avg 17 on my last trip to texas. or if someone knows of a website that can calculate for me that would be great also...i havent pulled much, just a few cars out of the ditch in the snow