As a senior citizen on fixed income and an ardent RVer, I am on a quest to gain the best milage from my RV. I have a 1997 Coachmen 23' Catalina (class C) powered by a Ford V10 engine. I have taken care to have the engine, tires and vehicle well maintained and in tiptop condition and consistenly get about 10 -11 mpg. After talking with outhers about this engine and chasis, Ford E 350 @ 10500lbs gw, I am getting good mileage but I really want to try to improve it further. My current strategy is to reduce my road speed down to an optimum point to squeeze the very best mileage possible from the rig. I currently keep my speed at approx. 60 mph but am willing to reduce it further if I would get better mileage. So, what speed would you suggest? Since I am retired, I am normally not in any hurry to get anywhere if it will allow me to continue to use the RV.