You could go with a Ram 2500 Hemi if you're not towing too far. The Hemi sucks down fuel but at 390hp/420tq it will easily tow your boat.

Well lets see ...... you can get an F150 with 6.2L Gas and a big tow that will haul 11K with no problems or the F250 with the 6.2L Gas. For pulling 9K you dont need the F250 with 6.7 Diesel unless you just want/have to have it. Diesel costs more to buy not to mention maintenance. Fuel savings on Diesel wont payback unless you are doing 50K Miles a year. Yes, the 5.4 isnt best in either the F150 or F250 but the new 6.2L kicks some mighty butt.

As stated, if it's not a daily driver and for occasional towing a big gasser is fine (but not the 5.4). If used find a V-10 and prepare to get 8mpg....still cheaper than buying a diesel.

6.2 is badass for sure