ok.
here's mine.
1. Lower drag tires
I ditched the all-terrains and went with a more dual-purpose tire.
Goodyear Silent Armors came off (worn out @ 55,000 miles) and a set of Wrangler SR/A's went on..
2. Synthetic driveline fluids
Keeps stuff flowing in cold weather not only helps economy, but longevity of parts & systems
3. Filters
I change all my engine filters at least once a year
4. CHANGE IN DRIVER HABITS
I started using the overhead Lie-O-Meter to take "instant" mpg readings while I was travelling on different roads and at different speeds.
I then coupled this with the tachometer readings in & out of OD.
From there, I could determine the most fuel efficient way to get around town, and the most effiecient speed to do it at.
Case in point; I fish the river about a half-hour from here... it's most efficient if I take County Roads to GET there, but the State Highway is the most efficient route HOME.
I know my truck gets better economy at 62mph than it does at 70, which is more economical than 80mph.
And I put a rotten egg under the go-pedal. 2000 rpm is all this thing gets, unless it's in first gear, then I let it climb to 2,500
and that ain't "stand on it til it hits 2,000rpm" either
it's "tip the throttle in until it hits 2,000rpm"
I drive like an old woman
4. Chip
I never would have believed it otherwise, I kind of did this out of desperation
hand calc'ed, I'm getting an honest 7 mpg more out of this POS since I put the chip in it last week.