GMC worked out the issue on the 2022 Sierra AT4 and now the 3.0-liter Duramax I-6 turbodiesel engine is standard on the 2024 AT4X and remains optional on all trims except for the base Sierra Pro.

The Duramax diesel ... Chevy Silverado 1500 or GMC Sierra 1500, but certain packages have the Duramax either standard or an option, such as the Silverado RST or Sierra AT4. These will tend to ...