The package is claimed to be the most off-road capable model in the Sierra HD lineup.
Initially available for the Canyon and Sierra 1500, the All Terrain X package pairs a blacked-out exterior with functional enhancements that help further ruggedize the heavy-duty pickup.
The dark color theme extends to the 18-inch painted aluminum wheels, grille surround, door handles, side moldings, mirrors and front skidplate, among other design elements.
The All Terrain equipment also includes Goodyear Duratrac tires with aggressive tread patterns, GM's Z71 off-road suspension system, an underbody shield and an Eaton automatic locking rear differential.
On the inside, drivers are treated to a heated steering wheel, rear-vision camera, adjustable pedals, leather-appointed seats, heated front seats and an eight-inch infotainment system.
The All Terrain X is available for the 2500HD crew-cab 4WD variant, powered either by a 6.0-liter gasoline V8 or GM's new Duramax 6.6-liter turbodiesel mill with 445 horsepower and 910 lb-ft of torque.
The company has not yet announced pricing or launch details for its latest blacked-out truck.