We drive a 2016 Excursion 35E with a 340 Hp Cummins ISB. Coach weighs loaded around 25,000 and we pull a CRV which is around 3500 loaded with gear. The CRV limits top speed to 65 but otherwise we run the speed limit with cruise control and the mode switch on. Mileage is generally 9-10 calculated but sits at 10.3 on the dash gauge.