Saw a lot of posts thinking the 36 gallon tank in only available in the longer box trucks. That is wrong it is available in all sized beds and trim packages. It is also included in the maxtow package along with 3.55 e-locker rear (upgraded to 3.73 with HDPP), trailer brake controler, upgraded stabilizer bar, upgraded bumper plus all the stuff the standard tow package has.
I have a 36 gallon tank in my 16 f150 screw 2.7eco with 5.5ft box. Thats over 800 mile range since I can easily average 23 MPG highway.
You start playing with those turbos though and the Eco part goes out the window but you get happy with that right foot and gas mileage drops no matter what you drive. My 5.3 Silverado got 17 MPG highway if I tried real hard and I could watch the gas gauge drop like a rock when I floored it.