Improving fuel efficiency with heavy vehicles
I receive a publication for the heavy trucking industry's fleet operators and the current issue had an article on 121 ways to save money on fuel. Many were applicable to RV users, some are obvious and...
Forum Discussion
tegu69 wrote:travelnutz wrote:
So true that slowing down is the biggest fuel saver of all. More savings than all the other's mentioned combined!
The rolling resistance for a given vehicle setup is constant whether at 5 MPH or 80 MPH. However, the air/wind resistance multiplies as speed increases. Like about 4 times the air/wind resistance going from say 40 MPH to 80 MPH and it takes a lot more fuel accordingly to overcome that greatly increased resistance while only gaining a mere 40 MPH. Also saves on brake, tire, and engine wear and vastly increases safety when emergency braking and accident avoidance actions are taken. It's WIN WIN WIN!
While I would agree that slowing down(to a sweet spot, not 40mph) is a big fuel saver, I don't think its the biggest. What about wind. Recently, we were traveling for several days into a 30-35 mph wind. I was getting about 6 1/2 to 7 mpg. Later on return trip we had a stiff tail wind and I got almost 12mpg. You might say that there is nothing you can do about that. Actually there is. I got on the road earlier with the headwind and then stopped before the wind really got cranking in the afternoon.
Well, it's true wind has a lot of influence on MPGs, but the relative speed you travel remains just as important. To Wit: Driving into a 20 MPH headwind at 55 MPH equates to using fuel to overcome a 75 MPH combined windload. Traveling into the 20 MPH headwind at 75 MPH equates to overcoming a 95 MPH windload. No?
