theoretical build for best fuel mileage???

[wide body]

what would be the best year of ford SD powerstroke to start with if i was to "build" a truck with MAX fuel mileage being the end goal. i know it would be a pre '08, but would the 7.3 be a better candidate than the 6.0? I'm sure a 2 wheel drive, with 3.55 gears (or even "higher" if they were offered) would be best. i'd want to stick with crew cab or course and auto trans.

any ideas?

[ryan.sampson]

for a basic build? i'm no professional but i don't see how the 6.0 could come close to a 7.3 as far as mileage

[hammett88]

um.. 6.4 with intake and deletes and run the highest tune in an xlt so you get the 3:15 gears or whatever they are .. they're crazy high and run stock tires..

[wide body]

i thought about the 6.4, but i'm still not convinced i want to do a delete. we have smog checks here and they are pretty thorough with the inspection.

i didn't realize there was even an option of 3.15s!!! that would be GREAT! the truck would most likely not be used for any tow duties whatsoever so the higher the gear the better.

whether i went with an '08+ or pre-emissions truck, do you guys think i could get to mid-high 20s for mpg if i used a 2wd, crew cab, short bed, bed cover (either tonneu or shell), slightly lowered, CAI, tuner and exhaust?

i'm looking at trying to get my wife out of her tahoe and into a diesel