Did some real life monitoring to verify MPG at various highway speeds . 2021 6 limited, 6800 miles. So flat straight road , about 20 miles at 60 mph gave me 26.9 mpg. Later on a different trip, 0n I-75, speed limit up north is 75. I did 79 mph for again about 20 miles, not as flat. I got 21.6 mph. Above 65mph, the MPG drops quick and in a big way ! Not too bad for a good size 4x4 .