Grit dog wrote:
Towing mpg will be much more speed dependent than the weight or size of the trailer (within reason), I believe. Have had 2 - 6.2 Fords and pulled several different trailers with them from small stuff to 14klb tag trailer with steel on it to 32' enclosed trailer, similar to a TT.
Pretty much didn't matter what went on the hook, once it was there, mileage was 10mpg or less. 8ish if I had my foot in it. Closer to 10 if going 55mph.
Frontal area can be reduced with some variety of pop up trailer. Other than that, you can't control any important factor other than your speed. Climbing grades and a headwind are factors mostly out of your control.
I have towed travel trailers with a variety of vehicles, all over the country. MPG from 6 to 14, overall average 10.
Generally stay at or under 80% of your tow ratin6, for a good experience.