Since its introduction in 2022, the off-road-focused GMC Sierra 1500 AT4X has exclusively employed GM’s familiar 6.2-liter gasoline V-8. The AT4X model is now getting a welcomed powertrain addition ...

The 2024 GMC Sierra AT4X is getting an upgraded powerplant for the new model year. Where it once solely featured GM’s 6.2-liter V8 truck engine, it’s now set to offer Duramax diesel power as standard.

The most extreme version of the Sierra 1500, the off-road-capable AT4X trim, will now be offered with a fuel-sipping 3.0-liter Duramax diesel engine. The torquey unit will come as standard on the 2024 ...

GMC’s off-road-focused AT4X lineup comes in three sizes: the heavy-duty Sierra HD is the largest, the mid-size Canyon is the smallest, and smack in the middle is the full-size, light-duty Sierra 1500.