GMC Takes Heavy Duty Further Off-Road with First-Ever Sierra HD AT4X and Extreme AEV Edition

  • Enhanced off-road capability matched with available 18,500-pound max trailering1
  • Offers the most trailering tech in its class2 and first-class luxury features
  • Specialized AEV Edition offers extreme capability and confidence off-road

GMC first elevated key off-road truck segments with the premium and capable Sierra 1500 AT4X and Canyon AT4X. Today, GMC announced the next step with the first-ever 2024 GMC Sierra HD AT4X — featuring the Sierra HD AT4X AEV Edition — a truck that enables adventurers to go further while still having the towing capability essential for heavy duty haulers.

The Sierra HD AT4X bolsters GMC’s lineup of premium off-road trucks, balancing increased off-road capability, smooth on-road handling, offering the most trailering technology in its class2 and first-class luxury and comfort features.

“GMC’s AT4X trim, which will be available across the entire GMC truck lineup, offers customers more premium choices when it comes to ‘do-it-all’ capabilities,” said Duncan Aldred, Global Vice President of Buick-GMC. “Each model delivers unique strengths, with the all-new Sierra HD AT4X taking it to the max, giving our customers the most luxurious and most off-road capable HD we’ve ever offered. AT4X means you can conquer almost any terrain, in complete comfort and with the towing power to bring your recreational toys, gear or camper along for the adventure.”

AT4X: premium off-roading the GMC way

Building on the foundation of the revamped 2024 Sierra HD, which receives fresh design updates, new available premium interiors and an all-new tech-focused layout, the new Sierra HD AT4X’s highlights include:

  • Available 18,500-pound max trailering capacity1
  • Factory-installed 1.5-inch (38mm) suspension lift
  • Multimatic DSSV dampers
  • Rear e-locking differential
  • 35-inch Goodyear Territory tires
  • Specific front upper and lower control arms and specific steering knuckles
  • Larger steel transfer case skid plate and front aluminum skid plate
  • Unique Obsidian Rush interior featuring premium appointments like massaging, full grain leather-wrapped front seats

The Sierra HD AT4X also includes a new Off-Road Mode. When engaged, the Off-Road Mode adjusts various vehicle calibrations, such as the anti-lock brakes, traction control and stability control, to provide optimized performance when venturing off-road. Additionally, Off-Road Mode alters throttle progression and transmission shifts to allow for better off-road control and performance.

Extreme AEV Edition

The available AT4X AEV Edition adds robust stamped steel bumpers with integrated recovery points and front winch capability which provide additional driver confidence and protection. It also features heavy duty steel skid plates that help keep vital components such as the steering gear and transfer case protected on the trail. Additional features include unique 18-inch Salta wheels and unique exterior badging and interior cues.

“The Sierra HD is an ideal foundation when it comes to on-road performance, off-road capability and insane pulling power,” said AEV CEO and founder Dave Harriton. “As with the Sierra 1500 before it, we took AEV’s signature performance-driven approach and dedication to detail to elevate the aspects that off-road customers want and demand in their heavy-duty truck. The result is an awesome truck with capability and confidence in all the right spots.”

Heavy Duty capability, turbocharged pulling power

In addition to the standard 6.6L gas engine, the new AT4X offers the turbocharged pulling power of the available 6.6L Duramax Turbo-Diesel. Enhanced for 2024, it will deliver 470 horsepower and 975 lb-ft of torque, offering more power across the entire operating speed range.

Both engines are paired with an Allison 10-speed automatic transmission, which is designed to optimize engine power, torque and efficiency.

Confidence-inspiring trailering tech
Along with the rest of the 2024 Sierra HD lineup, the new AT4X offers the most trailering assistance technologies in the heavy-duty class2 as well as the available ProGrade Trailering System.

It includes a suite of available intelligent assistance technologies designed to help streamline the hitching and towing process, with integrated tools that can help enhance customers’ safety, and confidence, including available enhanced, industry-first Transparent Trailer Viewfor Gooseneck and Fifth Wheel Trailering, available Trailer Side Blind Zone Alert5 and new, available Adaptive Cruise Control5 with Trailering.

Additionally, there are up to 14 available camera views6 including Hitch View, Bed View with Zoom and Bed Hitch Guidance, and Rear Side View with Trailer Length Indicator.

First-class interior luxury and comfort
The first-ever Sierra HD AT4X offers the luxurious appointments and comfort in a premium, off-road-capable HD pickup, with the exclusive Obsidian Rush interior that features power massaging front seats and full-grain leather-wrapped seats throughout as well as authentic Vanta Ash wood décor and 12-speaker Bose® Premium Series audio system with Centerpoint surround technology. The AEV Edition also features the AEV logo on the front-seat head restraints and unique AEV-branded floor liners.

The centerpiece of the new cabin is an all-new, tablet-style 13.4-inch-diagonal infotainment3 touchscreen. It is complemented by a 12.3-inch-diagonal configurable driver information center and a 15-inch-diagonal head-up display. Together, they provide customers incredible levels of personalization and intuitive engagement.

Coming in Q3 2023
The 2024 GMC Sierra HD AT4X and AT4X AEV Edition are expected to arrive at dealerships in the fall of 2023. Pricing will be announced closer to the start of production.

About GMC
GMC offers a range of premium trucks and SUVs designed and engineered to the highest standard. With vehicles like the compact Terrain and full-size Yukon, all-new Canyon and Sierra light-duty, as well as the world’s first all-electric supertruck, the GMC HUMMER EV, our trucks and SUVs deliver GMC’s signature combination of intuitive technologies, precise engineering and premium execution. Built on a strong foundation of manufacturing trucks since 1902, GMC now sells in a dozen countries across the world. Details on all models are available at, Instagram at @GMC, Twitter at @GMC or at

About AEV
American Expedition Vehicles (AEV) has now been on the cutting edge of the 4WD industry for over 25 years, continuously pushing the boundaries of design and innovation. The goal has always been simple: provide the highest quality off-road parts and accessories available anywhere in the world, period.

1Sierra HD AT4X’s 18,500-lb max rating requires available 6.6L Diesel engine and conventional towing. Before you buy a vehicle or use it for trailering, carefully review the Trailering section of the Owner’s Manual. The weight of passengers, cargo and options or accessories may reduce the amount you can tow.
2Class is gasoline and diesel heavy duty pickups in the GM Large Pickup segment. Based on latest competitive data available.
3GMC Infotainment System functionality varies by model. Full functionality requires compatible Bluetooth and smartphone, and USB connectivity for some device.
4Safety or driver assistance features are no substitute for the driver’s responsibility to operate the vehicle in a safe manner. Read the vehicle Owner’s Manual for important feature limitations and information. Requires available accessory camera and installation. Not compatible with all trailers. See your dealer for details.
5Safety or driver assistance features are no substitute for the driver’s responsibility to operate the vehicle in a safe manner. Read the vehicle’s owner’s manual for important feature limitations and information.
6Safety or driver assistance features are no substitute for the driver’s responsibility to operate the vehicle in a safe manner. Read the vehicle Owner’s Manual for important feature limitations and information. Some camera views require available accessory camera and installation. Not compatible with all trailers. See your dealer for details.



2500HD Crew Cab Standard Bed (4WD)


Type: 6.6L V-8 gasoline or E85 FlexFuel
Bore & Stroke (in. / mm): 4.06 x 3.86 / 103.25 x 98
Block Material: Cast iron with nodular iron main caps
Cylinder Head Material: Cast aluminum
Compression Ratio: 10.8:1
Valvetrain: Overhead-valve, two valves per cylinder, variable valve timing
Fuel Delivery: Direct fuel injection
(hp / kW @ rpm):
401 / 299 @ 5200 (SAE certified – gasoline)
(lb.-ft. / Nm @ rpm):
464 / 629 @ 4000 (SAE certified – gasoline)


Type: Duramax 6.6L V-8 Turbo-Diesel
Bore & Stroke (in. / mm): 4.05 x 3.89 / 103 x 99
Block Material: Cast iron
Cylinder Head Material: Cast aluminum
Compression Ratio: 16.0:1
Valvetrain: Overhead-valve, four valves per cylinder
Fuel Delivery: Common-rail direct fuel injection

(hp / kW @ rpm):

470 / 350 @ 2800 (per SAE J1349)
(lb.-ft. / Nm @ rpm):
975 / 1322 @ 1600 (per SAE J1349)


Type: Allison® 10L1000 10-speed automatic
Gear Ratios (:1):  
     First 4.54
     Second 2.87
     Third 2.06
     Fourth 1.72
     Fifth 1.48
     Sixth 1.26
     Seventh 1.00
     Eighth 0.85
     Ninth 0.69
     Tenth 0.63
     Reverse 4.54
Final Drive Ratio: 3.73 (6.6L gas)

3.42 (6.6L diesel)


Front Suspension: Independent front suspension with torsion bars
Rear Suspension: Semi-elliptic, two-stage, multi-lead springs
Steering Type: Hydraulic power-assisted recirculating ball
Brake Type:


Hydraulic power-assisted Hydroboost brake booster, four-wheel disc brakes with ABS and Stabilitrak electronic stability assist
Brake Rotor Size (in. / mm): Front: 14 x 1.6 / 355 x 40
Rear: 14.1 x 1.3 / 360 x 34
Wheel Size: 18 x 9-in. aluminum
Tire Size: LT305/70R18 MT


Fuel Tank (gal. / L): 36 / 136 (gas and diesel)


Wheelbase (in. / mm): 159.1 / 4042
Overall Length (in. / mm): 250.7 / 6369 (AT4X)

252 / 6401 (AT4X AEV Edition)

Overall Width (in. / mm): 81.9 / 2079 (without mirrors)

105.1 / 2670 (with mirrors extended)

Overall Height (in. / mm): 82.6 / 2100
Front Track (in. / mm): 69.3 / 1762
Rear Track (in. / mm): 70.0 / 1760
Ground Clearance

(in. / mm):

11.6 / 295 (AT4X)

11.7 / 299 (AT4X AEV Edition)

Approach Angle (deg.): 31.6 (AT4X)

29.8 (AT4X AEV Edition)

Departure Angle (deg.): 25.7 (AT4X & AT4X AEV Edition)
Breakover Angle (deg.): 21.2 (AT4X)

22.6 (AT4X AEV Edition)


Headroom (in. / mm): 43.03 / 1093 (front)
40.12 / 1019 (rear)
Legroom (in. / mm): 44.53 / 1131 (front)
43.4 / 1102 (rear)
Shoulder Room (in. / mm): 66.02 / 1677 (front)
65.3 / 1659 (rear)
Hip Room (in. / mm): 61.18 / 1554 (front)
60.24 / 1530 (rear)


Base Curb Weight

(lb. / kg):

7516 / 3409 – AT4X gas

8237 / 3736 – AT4X diesel

7894 / 3581 – AT4X AEV Edition gas

8605 / 3903 – AT4X AEV Edition diesel

GVWR (lb. / kg): 10850 / 4921 – AT4X gas

11350 / 5148 – AT4X diesel

10850 / 4921 – AT4X AEV Edition gas

11350 / 5148 – AT4X AEV Edition diesel

Payload1 (lb. / kg): 3291 / 1493 – AT4X gas

3068 / 1392 – AT4X diesel

2912 / 1321 – AT4X AEV Edition gas

2701 / 1225 – AT4X AEV Edition diesel

1For comparison purposes only. See the owner’s manual and the label on the vehicle door jamb for the carrying capacity of a specific vehicle.


Conventional (lb. / kg): 16000 / 7257 – AT4X gas

18500 / 8391 – AT4X diesel

16000 / 7257 – AT4X AEV Edition gas

18400 / 8346 – AT4X AEV Edition diesel

(lb. / kg):
18000 / 8165 – AT4X gas

17300 / 7847 – AT4X diesel

16200 / 7348 – AT4X AEV Edition gas

14800 / 6713 – AT4X AEV Edition diesel