2019 Sierra Goes Off-Road With AT4 Model
The Sierra AT4 is GMC’s off-road version of the 2019 Sierra. The AT4 model comes standard with a 5.3-liter V8 engine with Dynamic Fuel Management, and there is also an available 6.2-liter V8 engine that produces 420 HP and 460 lb-ft. of torque. The AT4 has a modified front grille that differentiates it from the…