Originally Posted by Darkbloodmon
Stock engine besides intake and 4" exhaust no cats, no emissions systems (if your driving behind me you'd best use recirculate). Im getting 17.2 city(consistently) no straight hwy runs since the trip from the dealership which was 23.4 on back roads around 50-60mph which is the ideal cruising speed around 1500-2000 rpms. This is all as is from the dealership. I've only changed the fuel bowl filter and re oiled the air filter the old inline one from the DDRP needs to be replaced.
My '04 2500 Quad Cab with the 5.9 CTD gets similar mileage. About the same on the highway and a bit better in the city. Motor wise I believe it to be generally stock. I do have a K&N air filter tho. My exhaust is configured in a similar fashion too. While I don't generally "punch it", if you're behind me when I do, ya, roll up the windows and push the "recirc" button.
I remember once reading that the best milage for a particular vehicle will be obtained if you pretend that there is an egg between your foot and the "gas" pedal AND try not to break it!!! I generally avoid Interstate driving and try to keep my speed under 60mph on the highway. I use the "cruise control" most of the time. I DO use a fuel additive (PowerService). "Gray" bottle except in the Winter when I switch to the "White" bottle". Shell Rotella T6 synthetic.
Every once in a while I get the felling that I should buy a "tuner" or something else someone has suggested to "improve" my MPG. Usually tho, I just lie down until that feeling goes away.
If we look at $/mile instead of MPG, many of the mods that supposedly increase MPG will also increase $/mile and likely result in a net loss! Just sayin'.