Do airfoils save fuel pulling 5th wheel?
Have been looking for ways to save diesel on my Ford 2002 7.3 and the neighbor running a Duramax pulling a 30' 5th wheel said his on-board mileage calculator said he was saving 30% with a fold down airfoil he purchased at Camping World. That's pretty good if it's really true because when unfolded it is only a foot or a foot and a half high I believe. The 18 wheelers use them a lot so that should say something but I don't know what percent they claim they save.
Have any experience and if positive any place national that would sell them cheaper than Camping World?