No secret just keep truck tuned, tires inflated properly, and using gasoline with the least amount of ethanol possible. Also I live in the mountains of South Carolina so not many flat roads here. I'm sure having a 6 speed manual helps. Of course when I try to drive it like a sports car my mileage dips. Still the worst I have ever gotten even in the dead of winter was 14.2.
CHSEPK MPG's can vary greatly due to alot of factors, but I can only tell you what my experience has been with my vehicle.

 

Do share!

 

Hmmm...

 

If you're comparing the 3.7 and 4.7 then get the manual tranny w/ either b/c it will leech less of your power. The HP difference between the 3.7 and 4.7 isn't much pre 08 like superbike said 210 vs 230 but the torque difference is 235 vs 290 which is pretty big. Lowest mpg I've gotten w/ my reg. cab v6 is 16 and the highest is 19.5, but I think you could get very similar numbers w/ a 4.7 reg. cab w/ a manual tranny.

 

Wow you guy's do get decent mileage with the V6's. I agree the manual tranny must make a difference. It amazes me because my 02 Dakota was terrible but it was the older 3.9. Guy's with the 4.7 were getting much better numbers than my V6.

 

V6 horrible, V8 only bad.