Hey bud! I have been towing my 17' 1986 Bigfoot
around all summer, up and down Vancouver Island, up steep logging road grades, all kinds of places. I am using a 2.7L four cylinder Tacoma with a 5 speed Tranny. It is a 4x4 so I usually run in 4 low when on the small logging roads. I have found that 1st gear high range is too much to attempt the steeper grades towing the Bigfoot.
My normal empty mileage with the Tacoma is between 23 and 26 MPG (imperial) and 16 MPG when towing the Bigfoot. This is the same every time I travel with it.
I can maintain the speed limit when traveling on the highway on everything except the steepest grades.
I will admit that a little more power would be nice if I could afford I new 6 cyl Tacoma I would do it.