I started out with a 2003 Ford F150 , Triton 5.4l V8,4x4 350ftlb torque, automatic,3.55 rearend,front discs, rear drum braking..standard suspension with aftermarket Bilstein shocks, front shocks, rear springs, 2003 226 Seafarer F250 Yahama, LoadRite Trailer..I mention the above specs because IMHO these are the keys to towing.."Engine power, suspension,torque and braking", I could tow the package , however I always bogged down on a hill or highway incline ( basically down to 30-40mph and never able to get past 60mph (not that u would want to) and accelleration was pretty poor. The low torque was a problem in this truck, braking was also an issue , eg. I had to be very careful anticpating downhill offramps. I was always bring pushed around while underway, meaning the boat/trailer pushed and pulled the truck, lots of sway and motion in the cab..this was due to the suspension and although the gas Bilsteins helped a little it was noticable..ramp launch and pulling was not an issue ( using the 4x4)..see below..
Recently I traded in the 03' F150 for a 2011 F150 EcoBoost (Twin Turbo Charged 3.5L V6,@365hp), 6-speed automatic,420ftlb torque, sway control, automatic engine speed control when towing option, 4x4, Disc brakes all around, 3.73 gear ratio, better suspension components(heady duty gas shocks, coil spring overshock front/wishbone, heavy duty leaf springs(rated at 11k towing lbs), this truck and configuration is a totally different experience in towing..it is amazing ..highway and ramp performance are outstanding ..meaning I can accelerate on demand, no longer bogg down and can maintain speed and stop the rig when I want without having to pump the brakes and always wonder what's ahead on the the off ramp..I am in control when towing.. I actually test pulled the boat with the Ecoboot and a 2011 F250 (gas engine) and the V6 Ecoboost was a better performer.
I'm not trying to sell the 011 F150..my point is , the keys are more than just power. its power plus torque, braking and suspension..all working together to make it happen. Yes..the 011 F150 towed the boat , however I now realize the differences with the Ecoboost V6 package.
Hope this information helps..
Regards...