From 38mpg to 45mpg on 07 hatchback by hypermiling and detailing exterior

[NYC-SE]

I find it unlikely that a 7mpg gain is possible from simply waxing the car. I'm sure a smooth surface will reduce drag but I suspect something else is responsible for your increased mpgs.

[dogsridewith]

Originally Posted by NYC-SE

I find it unlikely that a 7mpg gain is possible from simply waxing the car. I'm sure a smooth surface will reduce drag but I suspect something else is responsible for your increased mpgs.

OP's opening post notes a number of aero mods done after the detailing and before the test run...then finishes with a contradictory question:" Has anyone else experienced something similar after claying and waxing their cars? "

So, needs to repeat test w/ a modified dirty car. And/or a detailed stock car.