I drove one of these trucks recently. The drive train is high tech. I love the trans and it comes with a manual control on the shifter for the 10 speed. when you get up towards the rec weight it is going to make a lot of sense to slow down and use the gears. Otherwise you are going to create a tremendous amount of heat in that little engine and the trans. Heat is what shortens the life of trucks used for towing. If you take your time on the grades the rig is going to last a long time. If you "put your foot into it" all the time you can burn it up.
The new Ford F-150 really is a spaceship. I would never trade my clunky dated 7.3 liter diesel for one, but it is a great truck none the less. The $52,000 price tag stopped me in my tracks. I do not need a back up camera, an electric rear cab window or lots of other dodads.