I started a mpg test of my 6.0 diesel/automatic regular cab 4x4 F350 today. Here are the mods:
235/85 16 tires, broken in about 500 miles, replacing 265/75 16.
Radiator grill block (fabric)
Bed cover (plywood)
Removed spare tire from beneath truck and put in truck bed.
Relocated trailer harness out of airstream.
I'm driving several hundred miles on the highway in the next few days. I plan to obey the speed limits, mostly 65 mph. Just to see who pays attention to my posts, I'll send a crisp $10 bill to the person who guesses my mileage most closely. In case of a tie, the first person to post a guess wins.
Capitalism: The cream rises. Socialism: The scum rises.