I have a '11 F-150 with the new 5.0. I tow a Surveyor SV-264 at about 6000#. It performs OK in almost every situation. I towed it from Amarillo to Phoenix when I first got it and it did well, even on some steep grades around Santa Rosa, NM and points west of there. Not sure what your trailer weighs, but mine does fine. On the way back I had a 45 - 50 mph tailwind and decending grades most of the way... and got 15 mpg... Headwinds and such drop that to about 9 mpg, but I average 10 - 11... Enjoy!
J & D in Lovely Weatherford, TX
2016 Jayco White Hawk 28DSBH TT
2014 Ram 2500 Crew Cab 4X4 6.7L Cummins