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driving with the tailgate up imroves it. i saw that same episode of mythbusters. they did a full enclosed aerodynamic test and everything. with the tail gate up are circles around making a bubble right behind the cab. some of the new air coming over the top bounces off that and exits over the tail gate while some goes into the bubble. with the tailgate down the air just goes over and swirls around everywhere in no uniform whats so ever. as nascar people figured out. closing the air around your car is just as important as how you open it.
as for another thing to help mpg. a simple 2/3 or 2/2 drop would look nice and you could still use it as a truck. the less air going underneath would also help mpg
as for another thing to help mpg. a simple 2/3 or 2/2 drop would look nice and you could still use it as a truck. the less air going underneath would also help mpg
