2024 3.0 Duramax Mpg. Both got about 15 mpg towing but for a full size truck with more room than the. A friend of mine just purchased a 2023 at4 with the 3.0 duramax and he is getting consistent 30mpg highway.
Much of a recent trip. Did not burn any oil and def consumption was 1/2 tank for 2433 miles.