If you know your TV's torque curve, you can up/downshift to maximize torque at any time - particularly helpful when climbing hills, etc., reduced strain on engine, and decrease in speed while climbing. This apparently helps maximize fuel mileage, also. Of course, if you're driving an automatic, you may not have a lot of control over shift points. Our MH is on Mercedes chassis, and the transmission has tip-shift feature, which is very helpful controlling shift points.
Ed (N4RWU) & Becky Taylor
Mistie (Walks 4-down)