what do you use such large vehi for?
do you need them for work?
improve the FE on your cars look here first.
http://www.gassavers.org/showthread.php?t=4542
im sure you can make great strides with the vehi you have.
Is any drive opposed to driving a smaller for FE car?
Look around do some Searching.
look at tracking you FE so you learn what works and what isnt working.
or even a scan guage 2.
Ive been here a short while and have learned lots by reading what been already posted.
Fact of the matter is you will not see 45 or 50 .. mostlikely even 25 but every gallon is almost a 4 dollar savings.
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