Hey,I think it will depend on the weight of your trailer.Diesel will do better with a heavy load than gas because of the extra torque.My dad gets around 14 in his Ford Powerstroke,which is the same as my V6 Ford truck,but he can obviously pull a hell of a lot more than me.On a recent trip to the beach,my wifes Suburban got right at 20 pulling our popup camper.