2025 Chevy Duramax Mpg Chart. Chevrolet has made big improvements to the 2025 silverado hd 6.6 duramax turbo. The 2025 chevy silverado sets a new standard for gas mileage in large pickup trucks.

Though chevy’s and gmc’s 6.6 liter 6600 duramax diesel remains one of the most popular engines around, how much mpg can it really average? Here’s a breakdown of 2025 chevy silverado 1500 towing capacities.