First Tow 6.2 Gasser
2013 F250 Lariat 4x4 373 rear end. 5k miles on odometer.
I had 2009 F250 diesel but was never happy with it as far as MPG and towing. I towed a 24' center console boat with gross weight with trailer, full fuel and equipment of around 9k. 7 MPG is what I averaged when towing about 13 - 14 when empty. 26 gallon tank would not let me get far when towing which was another irritation. Putting auxillary tank in the bed and taking up space there was not an option for me (personal preference).
New sled is 31' center console with full fuel, trailer and equipment of around 11.5k. Towing with the 6.2 I average 7 mpg (65 mph) and I am impressed with the towing. It will take some getting used to the RPMs over the diesel but the power is there when I need it.
Mostly flat surface with quite a bit of side wind. I did not lock out any gears I just put it in Tow/Haul mode and let the tranny do what it is supposed to do. The truck mostly stayed in 4th gear with occassional 5th and more often 3rd than 5th when not in 4th.
The boat sticks up pretty high so there is a lot of drag resistance from the T-Top and windscreen.