Okay don't know bout you guys, but with my truck (no box) I get average of 12 mpg, half highway empty, half in town with loaded trailer. With the leaf box, get this- 8 mpg (technically 7.9) !!!!!!! using same half highway empty, half in town loaded. I'm stopping at every gas station i come to and the attendants tell me to shut off the truck because the pumps can't keep up LOL (j/k). This is a Ford 351 gas V8, EFI, and 5 speed manual trans. Pretty bad IMO. Plus it's a major pain to drive on windy days. Now I don't normally care since i just buzz around town with it so it's not terrible, but today i went on a road trip 2 hrs one way and i went through 30 gallons of fuel in about 4 1/2 hrs driving time Anyone else checked their mileage with leaf box?