Before you buy, I'd check into renting a like size/type unit. You might even be able to "test drive" what you are looking at. We bought a larger trailer, and pulled it with a 3/4 ton Suburban with the 454 we got 4-5 MPG. Later we bought the newer Burb with the later big gas engine. Fuel milage was 4-5 MPG. Back then our trips were 1500-2000 miles round trip. We then bought a Diesel P/U and the milage almost tripled (12-13). Then we bought the bigger 5th wheel.... It would have been cheaper if we tried them out before making our first purchase.