Well, by best mod to date is no longer working so well. Last week my motorcycle was stolen.
However, I made another improvement on the truck. It had these wheels on it when I bought it:
Heavy, steel wheels with a fairly deep dish to them. The tires needed to be replaced, so I decided to get some more aero wheels instead (sorry about the poor picture quality):
The 4WD trucks had taller tires and these aluminum wheels. Weight is nearly the same in spite of the larger diameter. The face is nearly flat, and the tires fill up more of the wheel well gap. All pluses in my book.
First full tank of gas with them yielded 19.2mpg! So, preliminary results are about 5% better than what I got with the steel wheels.
And I'm at about 22% better than what I got when I bought the truck.
Woot!
Mike