I believe the tech column of Trailer Life dealt with this issue a couple of years ago. Their response was about the same as skipnchar added in his comment. The amount of increase in mpg is very, very minimal and unless you drive thousands of miles per year as truckers do you are wasting time and money.
Another point is that unless you take it off it hurts your MPG when not towing. I knew several people during the gas crisis in the early 70s who towed RVs for various manufactures. The air deflectors became sort of a fad so they tried them. Within 6 months they took them off. It was just too much trouble to put it on when towing and off when not towing and then finding a place to store the thing. They also seemed to think that it didn't necessarily reduce the bugs on the front of the trailer but just moved the bug line higher. This was an issue for them because the driver had to clean the trailer before delivery.
Now they do work on large tractor trailers but the key thing that can't easily be duplicated with a pickup is that the good ones are located just inches from the trailer and importantly extend the entire width of the trailer.
USN Retired
2007 Cedar Creek 30 RLSTS
2008 F350, DRW, V-10, B&W hitch,
Pressure Pro, JT Strongarms
Offline
