At 3200 miles, I've seen an improvement from 19+ a couple thou ago to 20.7 last time I filled up.

Mixed 2-lane highway & city (suburban), rolling hills, I use the cruise alot (I really think that helps), and have been known to wait on accelleration for a hundred yards so I can do it downhill.

But then again, Night Armor cars have a lower ballistic coefficient so you automatically get better mileage!

I read somewhere that between 60 to 70 you use 25% more fuel consumption and between 70-80 you use 35% more fuel because of wind resistance. Makes sense to me. These trucks are as aerodynamic as a beveled brick. So I keep it between 60-65 and get good mileage.

Lately, I get about 20 - 21 MPG mixed city / highway, and -not- driving like an old lady...

My drive is 16 miles each way, mostly flat, with about 2 miles of freeway. Elevation here is about 640 feet. I can drive with the AC off (that time of year finally) so that probably helps too.

I have a 6MT 4x2 S with 4200 miles on it. I shift around 2k rpm's except when getting on the freeway - then just depends on what I'm getting into - sometimes keep in 5th at 2200 2300 rpms till around 65 mph, until I get to cruising speed and hold in 6th 2100 rpms at 70 mph.

On regular roads 30 - 45 mph I cruise in 5th or 6th, and keep my rpms around 1200 - 1800 depending on the angle of the road (hills here are more like unlevel surfaces), usually going about 5 mph over the speed limit.