Yup, so I must apologize. Apparently it is possible to get 20+ mpg out of a stock 07 F150... look for my concession blog to appear later on today with details of my findings...  

awesome!  

Check it...

http://blogs.fourwheeler.com/6274452/miscellaneous/how-my-ford-f150-fx4-got-20mpg/index.html  

Don't feel bad. I've been called a liar (and worse) for stating that I can get 20-21MPG from my TA, crusing at 85-90 on the interstate, so long as I keep my foot out of the throttle and accelerate at a rate that can be duplicated by normal cars. With 3.23 gears, 90MPH is a mere 2700RPM, which certainly helps. Do I do this very often? About as often as you're going to get 20MPG out of your F150, Iwould say. It's not nearly as much fun driving conservatively enough to get 20+ MPG. But it's possible.  

I still think you are a fibber about 20 to 21 MPG at 85 to 90 MPH. It is wishful thinking at best. Drag increases a lot over 65 MPH at at 90 is is quite high. Good "story" though. Next it will be 19 to 20 MPG at 100 MPH or maybe 30 at 65 MPH.  

no wishfull thinking....
my 82 vette and my 82 camaro both can get 20 also at those speeds, and both have crossfire injection.  

I could "maybe" see a vette as 80 to 85 because it is a lot sleeker than F-bodies but not on those others. Generally people tend to claim better MPG than they actually get. When I report a MPG figure it is over a 300 to 400 mile plus tank refill with mixed driving, not a top off.  

It's not crazy.  I have a 2004 F150 with a 5.4 with a lid over the bed and got 20 mpg highway. I put the cruise on about 67.  I usually get about 16 to 17 in the city.  No hyper driving just slow down a bit.