Not sure what to make of it, but I just turned 10,000 miles in my ‘22 1500 Laramie, 5.7 etorque, 4x4 and after virtually every refill showing between 15-16 mph all around and 10-13 towing our 5,000 lb. travel trailer, we started out on Monday with a full tank, drove from home at 2180 ft up to Lake Tahoe at 6,500 feet and back home, then another 125 miles to Sacramento and back home.
The mileage readout is sitting at 19.3 mpg.
Maybe 10k miles throws a switch. Or, maybe the gas predictor is on the fritz.