Several tips on improving MPG ( article )
 

This article is good reading.
It covers several areas.
http://forums.hotrod.com/70/1344701/...ing/index.html

And yes, it is on HOT ROD magazines website :)

( Perhaps this would be better in another forum, since it covers so many topics )

A few interesting quotes from the article :

According to Ford
Motor Company engineer Steve Wegryn:
"an inch of ride height increase degrades the coefficient of drag by about
10 drag counts [.01]".

Unlike the Mythbusters TV show test of up/down tailgates on a 2005 Ford F150
these students found a very slight advantage to having the tailgate down
but the difference is so slight to be not important The new design F150 does
have significantly deeper pickup bed, higher sides, and taller tailgate than a
1998 Ram so that might explain the slight difference. Any automotive engineer
would tell you that having a pickup run completely out of fuel on high speed
interstate highway might make for a Dramatic! Entertaining! TV show so that
advertising can be sold for big $, but it is a totally undependable way
to measure MPG carefully and with repeatability. (Note that the Mythbusters
built a 'water flume' out of plywood and an electric boat trolling motor for
their toy F150? They almost certainly got this idea from the ASME prize
winning
website using the toy Dodge Ram listed above)


Switching to synthetic lubricants - - engine oil, diff, synthetic Mopar-spec
transmission fluid, and syn greases in wheel bearings is good for 2-5% MPG
improvement. That is only about 0.5 mpg but every little bit helps.

The 2nd Gen Dodge Ram Diesel that set the Bonneville speed record had
'Mooneye' wheel cover discs. These are supposed to reduce aero drag
by 1-2% but hurt brake cooling. I also notice this Ram had mirrors and
windshield wipers removed.