I use the trip 2 odometer reset on def fill up at truck stop and usually let it go to under half never more than 4 gal and usually about 1000 miles. Mine is a 2016 2500 and pull 11K snowmobile toy hauler 6-7 month a year about 700 miles a month to the mountains from Laramie WY Turck average about 11 mpg fuel in colt temp and most times 30 + mph wind, some days I get lucky and have 2-6 mph wind!
gtwitch in wyoming