A lot of the Ecoboost F150s have been sold on the towing capacity pitch. You could easily end up with 9000 lbs of trailer. They are supposed to be rated to pull 11,500 pounds and they may do it, but the Tundra was also used to pull the space shuttle and you would not want to do that on a steady basis. While the Ecoboost may be a very capable engine, think about those turbos running full-tilt boogie all day long. That is a lot of stress and a lot heat for a 6 cylinder engine to handle, and that's not even getting to the payload issues yet. Bottom line, that trailer cries for a 3/4 ton truck