I get close to that in my 2020, same engine, 4x4 with 3.55 gears and factory tires. Drove to Alabama and back last month and kept it under 76mph on Interstate, around 60-65 on other highways. Some running around town for a few days while I was there. Computer said 22mpg average for the trip, and I have found it to usually be about 1mpg above my hand calculations. I drive a fair bit of highway every week, generally at 60-65mph, and my readout generally hangs around 22mpg for the mixed driving of a 36gal tank. More like 24mpg if it is straight 60mph highway trips with no load. I find it fairly impressive, considering the size of the truck and the power. The turbos are sometimes audible when I hit hills, and this often results in the truck staying in 10th gear instead of downshifting. The truck will likely get a winch guard in the next few months, along with some lift spacers to keep the front end near factory height. I expect to lose a bit of MPG as a result. If I bump up to a slightly taller tire when these wear out, I'm sure that'll cost me a bit too.
