I've managed to get a little over 20 before...Keep in mind this was in the wintertime with no a/c and I was on the interstate with the cruise set. On average, highway and city driving combined with the ac running and I usually pull a trailer once or twice per tank, I typically averaged 16.5.

When I new something was screwey was when it got only 257 miles on a full tank of gas. Then I checked it and got 13.87 on interstate with cruise set and no a/c on. That was a problem!
I babied it for a while and ran with no ac after resetting the computer and it got a little better than 18 mpg yesterday. Now turning back on the a/c, I should be back to normal at around 16.5

 

I have to agree. The mileage on these trucks suck. I bought the 4.6L thinking I'd get better mileage (since I don't pull anything with my truck). Based on what I'm seeing it doesn't make much of a difference.

I'm averaging around 15-16 driving a "mix" of highway and city.

J

 

Well I hate to inform every body but what truck out there does get great gas mileage. Ford,Dodge,or Chevy. The way you drive can make a difference too. Heavy on the foot can make a huge difference. Going against strong winds that can make a difference too. Yes even different types off gas. Ive had certain kinds off gas that gets great gas mileage an others that dont. With the fuel situation the way it is. That will happen. I would go over several months before any kind off judgement on gas mileage. Tjere are so many variables.

 

Does anyone feel that the higher octane fuel is woth the price difference....Meaning does it increase you milage enough the warrant the difference..I get abot 16-17 constantly.....highway/city driving...