We have a 2004 26q fleetwood jamboree with the v-10 and just return from our longest trip of 1800 miles, with towing a 2012 Toyota Camry. I kept my speed under 65 and drove without the cruise in the hills. The total trip I average 7.9 mpg. I filled up every 360 miles with 45-46 gals each time. I also ran the a/c on the motor and no gen. I would love to know how some people with larger class c or getting 10 mpg.