I drove 398 miles on 17gals. of fuel! It was all interstate with very little load, @76deg. and didn't go much faster then 63 mph. but wow. The trip back I went 70-75 mpg and still got 17.5 mpg, not bad for a F350 4x4.

 

Stock tire size?

 

Hand calculated or lie o meter, I thought I was the shizznit when I first got my truck and did the maintenance and minor mod, then took a friend with a 6.4 for a ride and showed him 25.1 on the lie o meter

 

Stock tire size, no lift, hand calculated. The lie-o=meter actually said 20.5mpg and I was hoping it was right. Man was I surprised.

 

Must have been down hill on the way and up on the way back.

Seems like every time I start a trip at 60-65 my finger gets a twitch and keeps hitting the accel button on the cruise until finally I settle in around 80-85.

 

It was hard to keep from doing that too but hearing others on this site saying if you keep the rpm/boost down, speed versus wind resistance etc. you could pull some good mileage. So I set out to see how good. I was in no hurry going so I had the time to test but on the way back I ran normal but it still did pretty good. I had a Expedition in the past and the best I ever got with that was 17mpg -down hill with a 30mph tail wind.