"Bill Daniels" bildan@comcast-dot-net wrote in message
. ..
You guys haven't mentioned the biggie - roof racks. Removing the cross
bars
from my Grand Cherokee added 2MPG. Glider pilots look at roof racks and
see
open air brakes. I can't believe the number of vehicles I see in Denver
with ski racks in July.

Then, of course, you can park the truck. I understand that trucks have
very
low drag when parked.

If the vehicle has a MPG computer, you can see what speed does to MPG. At
65, my Jeep gets 19MPG. At 55, it gets 24MPG. At 45, it gets 36MPG. If
you do the numbers, saving two minutes by driving fast costs big time.
Those are REALLY expensive minutes - more than the rental on some
airplanes.

Bill Daniels


Those numbers really bother me. The numbers are all fairly low; but the
curve shape fits aerodynamic drag, with no other influence such as tires or
"pumping losses." In effect, the numbers fit a much larger, but
aerodynamically atrocious and very lightly loaded vehicle. Therefore, I
really doubt that your mileage computer is telling you the whole truth.

Have you 1) verified you odometer against at least 10 miles of highway mile
markers, 2) verified your speedometer reading at 60MPH as a result of the
same test, and 3) checked the cumulative fuel mileage, as shown on the
computer, against your fuel mileage calculated in the usual way?

Peter