The results (drumroll please)? A very comfortable 45 mile range over a period of about an hour and 10 minutes, with the truck still comfortably maintaining 55 mph when I pulled in the driveway.
I was, needless to say, quite pleased.
Next up: The 70 mile roundtrip commute to my summer job, in rush hour traffic. I hope to undertake this expedition tomorrow morning, and I should have the results sometime tomorrow afternoon. I'm excited. Stay tuned!