as one person very knowledgeable told me last year "it's important how much you can pull but it's more important how much you can stop". I had a F150-everyone i talked to(none pulled trailers, including the dealership) said i was good up to 13,000#. We took a trip to Florida, April, and hadn't made it 100 miles my wife says "your gonna need a bigger truck". Our TT is 6840#, and fortunatley we found a F250 w/6.7. While we were going across Raton Pass, WYoming, and Teton Pass i knew we made a great decision. SO as Gronk says without knowing your intentions its hard to say. You will probably get the TT up the hill but you could have issues trying to stop it going down grades.
FYI--the Tow/Haul and engine break were magnificent on 8%-10% grade on Teton pass.