Max Trailer Wt. Recommendations for F-150 5L or Eco/Boost

I can't tell you about towing but I can tell you about lack of MPG's. I borrowed a friend of mine's F150 Eco-Boost and went on a 400 mile ride. 95% was the interstate. I had all I could do to get 16.5mpg empty. I have driven that same route many times with my DRW Duramax and get 18-19mpg. My point is, that if I were in your shoes I would steer clear from the Eco-Boost.