Wind deflectors
Does anyone know if those wind deflectors have any effect on gas mileage .. Will these deflectors give you better gas mileage and if so how much
Forum Discussion
In order to get any SIGNIFICANT difference you'll need a very LARGE deflector. I used to travel with my 8 foot bed cover (solid fiberglass) propped open, giving me a 4'X8' wind deflector and got a couple of miles per gallon improvement in towing my 34 footer with the 5.4 V8 engine. For the MOST part it's not practical to drive around with that much deflector and much less will of course return much less. It will be hard to justify the cost unless you get a VERY good deal on the deflector (my cover cost me over $800.00) but I had it anyway to cover gear in the truck (which it no longer did when it's propped open) :)
AS for a "topper" they might possibly improve wind resistance a little bit but you'll also be hauling more weight so my best estimate is they're about a push. A TONNEAU cover will NOT increase your mileage any measurable amount as you no longer get the vacuum effect of an open bed with tail gate closed, which is proven to be the MOST economical but the differences are minimal.
Good luck / Skip
AS for a "topper" they might possibly improve wind resistance a little bit but you'll also be hauling more weight so my best estimate is they're about a push. A TONNEAU cover will NOT increase your mileage any measurable amount as you no longer get the vacuum effect of an open bed with tail gate closed, which is proven to be the MOST economical but the differences are minimal.
Good luck / Skip
