ok i have been studying on here for awhile different thing you have all asked about regarding mileage. with my 11 350 dually, 4x4, 3.73 gears, i get 15-17 driving respectively mixed city and highway. when i decide to hot rod it it drops quick. but pulling a small trailer, and i mean small ( 10 foot) with my utv on it the mileage drops down to about 10-11 almost like the trucks programmed to consume more fuel. any ideas why? there is no gate on the trailer, trailer has no electric brakes to stick on,and yes the tires are aired up properly on the trailer.this is on the highway driving to, we usually ride at a park about 100 miles away from home, so i set the cruise and i go.speed also doesn't affect it so it seems. at 70 exactly the mileage is around 12.5 with the trailer and utv on it. empty it will hold right at 17 on the same road, same speed.i even removed the windshield from my utv thinking it was a wind drag, no difference. any ideas dave?