I found this wing on Craigslist for $75. I had it painted to match the lower trim on my Excursion. I don't know who made it, but it was probably from the late 70's or 80's? I gained .5 mpg. One long trip and it paid for itself! Plus you could feel the engine wasn't working as hard due to the air flowing up and over the trailer instead of hitting it. Also the bug line at the top of the trailer disappeared showing that it did indeed move the air up and over the trailer. But it has to be mounted as close as possible to the trailer. If you have a pickup and put it on the top of he cab, it won't work as well.
