GM will add its famous AT4 trim level to every GMC’s vehicle in the next two years. The upcoming 2021 GMC Sierra AT4 will be one of the most exciting ones. Interestingly, but 2020 Sierra AT4 is already on the markets. Moreover, even Sierra’s HD lineup offers an AT4 variant. Shortly, AT4 will become available on Acadia and all other models that are currently offering the All Terrain trim level.
Basically, AT4 treatment replaces the All-Terrain models. The 2021 model will gain a couple of important upgrades. Moreover, Sierra AT4 will look to rival Ram 1500 Rebel pickup truck.

2021 GMC Sierra AT4 Design
The forthcoming 2021 GMC Sierra AT4 is an off-road-oriented pickup truck. It does look more aggressive than the base trim level. This model comes with a commanding presence that still looks subtle rather than brutal and dramatic. AT4 edition is available in blacked-out features, and it provides upscale design. Dark chrome finishes are available, mostly around the front and rear bumpers. Even the grille surround is painted in body color.
The black grille looks impressive and below that you’ll see distinctive red tow hooks. As for the exterior features, Sierra AT4 offers new 18-inch wheels that are wrapped in Micheline all-terrain tires. Moreover, 20-inch wheels are optional and are looking incredible. Off-road suspension, Rancho shocks and Eaton locking rear differential will provide amazing off-road experience.

List of Interior Upgrades
Beside amazing design and performance, the new 2021 GMC Sierra AT4 will also get an improved interior. That mostly includes technology upgrades. For a start, this pickup comes with the Traction Select System. This system adds off-road mode as well, as standard. Moreover, hill descent control and hill start assist systems are standard as well.
An exclusive 15-inch head-up display provides a better user experience and is simple to use. The very same display adds an inclinometer that sits in front of the driver. A Surround Vision setup is available too, and it uses up to 15 cameras.
2021 GMC Sierra AT4 Engine
The all-new 2021 GMC Sierra AT4 is equipped with a 5.3-liter V8 diesel powertrain. This engine delivers 277 horsepower and 460 lb-ft of torque. However, the AT4 variant will add another 37 lb-ft thanks to the latest tuning. In Sierra HD versions, this unit can tow up to 21,300 pounds and a maximum payload of 4,400 pounds.
According to numerous experts, Sierra AT4 delivers a better ride than the Silverado HD. However, this model will directly compete with Ram Rebel pickup truck that also uses a diesel powertrain. A four-wheel-drive system is standard, and a diesel engine will deliver 22 mpg combined. Lastly, a 10-speed automatic transmission is offered as standard.

Price and Release Date
The price of the all-new pickup truck starts at $56,000. The 2021 GMC Sierra AT4 is priced in line with the rest of the competition. As we mentioned, GM will completely replace the All Terrain trim level with the AT4 variant. That means most of the company’s models will get the AT4 treatment in the next year or two. As for the Sierra AT4, this model will go on sale in the second half of 2020.