You can definitely do that towing with a Ranger, esp the 2.7L. I towed my 718T across the midwest to the SCCA Nationals in Lincoln Nebraska (two days of driving) and the truck didn't break a sweat. I tow my car around quite a bit with it and am impressed by the mileage also - Sometimes I'm...
I've noticed wind makes a massive difference in my truck. I have seen up to 27mpg on interstate stints where I had neutral/tail winds (and 17ish going the opposite direction). 75mph. 2.7L - Very new (<200 miles on truck!)