My owner's manual says not to tow at all. I have a 2011 Fusion SEL w/3.0 6cyl.
I personally think that is ridiculous. If you have 240 HP, 4 wheel disc brakes and you are only using a class I hitch, then it is no different than having 5 adults (1000lbs) and say their luggage(250lbs) in the trunk. You can get a small trailer (300lbs) and say put a Harley (650lbs) on the trailer and you're at less weight.
I am getting an etrailer hitch myself.