From Terrain to Sierra HD: Your 2026 GMC AT4 Buyer's Guide

The AT4 badge signals GMC's focus on off-road capability and rugged performance across multiple vehicle categories. For drivers in Mississauga and throughout Ontario, the 2026 model year brings six distinct AT4 models, each engineered to handle challenging terrain while delivering the refinement expected from GMC. From compact SUVs to heavy-duty trucks, this guide breaks down every AT4 option to help you identify which model aligns with your driving needs.

2026 GMC Canyon AT4 & AT4X

The Canyon brings midsize truck capability with serious off-road credentials. Both AT4 trims feature 4WD-only configurations in Crew Cab with Short Box layout.

Canyon AT4

The Canyon AT4 delivers 310 horsepower and 430 lb-ft of torque from its TurboMax 2.7L turbocharged 4-cylinder engine. The 2-inch factory lift and off-road suspension provide 244 mm of ground clearance front and rear. An automatic locking rear differential and two-speed Autotrac transfer case manage traction across varied surfaces.

Key specifications:

• Engine: TurboMax 2.7L Turbo I-4
• Power: 310 hp @ 5600 rpm / 430 lb-ft @ 3000 rpm
• Transmission: 8-speed automatic
• Fuel Economy: 13.6 L/100 km city / 10.7 L/100 km highway

Canyon AT4X

The AT4X extends capability with a 3-inch lift system and Multimatic DSSV dampers. Ground clearance increases to 272 mm at both axles. Full-locking front and rear differentials provide maximum traction control, while Baja mode optimizes performance for high-speed off-road driving.

Key specifications:

• Ground Clearance: 272 mm front and rear
• Suspension: DSSV Multimatic dampers
• Differentials: Full-locking front and rear
• Fuel Economy: 14.1 L/100 km city / 13.8 L/100 km highway

Canyon AT4 vs. AT4X Quick Reference

2026 GMC Sierra 1500 AT4 & AT4X

Full-size truck capability pairs with off-road engineering in the Sierra 1500 AT4 lineup. Both trims feature Crew Cab configuration with 4WD and offer two engine choices.

Sierra 1500 AT4

The Sierra 1500 AT4 provides two-inch factory lift with off-road suspension tuning. Standard power comes from the 3.0L Duramax Turbo-Diesel I6 producing 495 lb-ft of torque, with an available 6.2L EcoTec3 V8 delivering 420 horsepower. The automatic locking rear differential and two-speed Autotrac transfer case manage power delivery across surfaces.

Key specifications:

• Standard Engine: 3.0L Duramax Turbo-Diesel I6 (495 lb-ft torque)
• Available Engine: 6.2L EcoTec3 V8 (420 hp)
• Transmission: 10-speed automatic with Electronic Precision shift
• Ground Clearance: 282 mm front and rear
• Fuel Economy (Diesel): 10.7 L/100 km city / 9.3 L/100 km highway
• Max Towing: 4,082 kg (9,000 lb)

Sierra 1500 AT4X

The AT4X adds Multimatic DSSV dampers and driver-selectable full-locking front and rear differentials. AEV hot-stamped boron steel skid plates protect critical components. Ground clearance increases to 292 mm. The AT4X features Obsidian Rush full-grain leather seating and a standard 15-inch multicolour Head-Up Display.

Key specifications:

• Ground Clearance: 292 mm front and rear
• Differentials: Driver-selectable full-locking front and rear
• Suspension: DSSV dampers with 2-inch lift
• Skid Plates: AEV hot-stamped boron steel
• Fuel Economy (Diesel): 12.2 L/100 km city / 12.0 L/100 km highway

Sierra 1500 AT4 vs. AT4X Comparison

2026 GMC Sierra EV AT4

The Sierra EV AT4 brings electric power and off-road capability together in a fully electric pickup. This model features dual-motor e4WD and specialized terrain management systems.

Power and Range

The Sierra EV AT4 delivers between 605-760 horsepower and 605-775 lb-ft of torque depending on battery configuration. Three battery options provide range flexibility:

• Extended Range: Up to 611 km
• Max Range: Up to 769 km

Off-Road Features

The Sierra EV AT4 includes a 2-inch suspension lift and 35-inch all-terrain tires. Standard 4-Wheel Steer with CrabWalk diagonal drive mode provides precise maneuvering at low speeds. Terrain Mode integrates with one-pedal drive and automatic braking for maximum control on uneven surfaces.

Key specifications:

• Power: 605-760 hp (depending on battery)
• Torque: 605-775 lb-ft
• Battery Options: Extended Range, Max Range
• Max Towing: 5,534 kg (12,200 lb)
• Ground Clearance: 2 inches additional vs. standard Sierra EV
• Standard Features: 4-Wheel Steer, CrabWalk, Super Cruise (3-year plan)

Sierra EV AT4 Battery Comparison

2026 GMC Sierra HD AT4 & AT4X

Heavy-duty capability pairs with off-road engineering in the Sierra HD lineup. All models feature 4WD Crew Cab configuration with two engine choices.

Sierra HD AT4

The Sierra HD AT4 is available in 2500 HD and 3500 HD SRW configurations. Off-road suspension with Rancho twin-tube shocks and standard skid plates protect components during trail driving. Two engine options deliver different capability profiles:

6.6L V8 Gas Engine:

• Power: 401 hp @ 5200 rpm
• Torque: 464 lb-ft @ 4000 rpm

6.6L Duramax Turbo-Diesel V8:

• Power: 470 hp @ 2800 rpm
• Torque: 975 lb-ft @ 1600 rpm

Capability (2500 HD AT4):

• Max Payload: 1,598 kg (3,524 lb)
• Max Conventional Trailering: 9,072 kg (20,000 lb)
• Max Gooseneck/Fifth-Wheel: 9,612 kg (21,190 lb)

Sierra HD AT4X

Available exclusively in 2500 HD configuration, the AT4X features a 1.5-inch factory lift with Multimatic DSSV dampers. The 35-inch Goodyear Territory MT tires mount on AT4X-specific wheels. A rear electronic-locking differential and steel transfer case skid plate provide additional capability.

Capability (2500 HD AT4X):

• Max Payload: 1,499 kg (3,304 lb)
• Max Conventional Trailering: 8,392 kg (18,500 lb)
• Max Gooseneck/Fifth-Wheel: 8,165 kg (18,000 lb)
• Ground Clearance: 295-299 mm

AT4X AEV Edition

The AEV Edition package adds stamped-steel front and rear bumpers, AEV Salta wheels, additional skid plates, and AEV embroidery on interior surfaces.

Sierra HD AT4 vs. AT4X Specifications

2026 GMC Terrain AT4

Compact SUV dimensions pair with off-road capability in the Terrain AT4. This AWD-only model features a lifted ride height and all-terrain tires.

Powertrain and Efficiency

The Terrain AT4 uses a 1.5L turbocharged 4-cylinder engine producing 175 horsepower and 203 lb-ft of torque. An 8-speed automatic transmission manages power delivery to the Active Torque Control AWD system.

Fuel Economy:

• City: 9.9 L/100 km
• Highway: 8.9 L/100 km
• Combined: 9.4 L/100 km

Off-Road Features

The AT4 trim includes a lifted ride height, front skid plate, and underbody protection. Red recovery hooks and all-terrain tires distinguish the AT4 from standard Terrain models. An AT4-exclusive drive mode optimizes traction and throttle response for off-pavement driving.

Key specifications:

• Engine: 1.5L Turbocharged 4-cylinder
• Power: 175 hp @ 5800 rpm
• Torque: 203 lb-ft @ 2000-4000 rpm
• Drivetrain: AWD (Active Torque Control)
• Seating: 5 passengers
• Cargo: 844 L (seats up) / 1,798 L (seats down)

Technology and Safety

The Terrain AT4 includes a 15-inch diagonal infotainment display with wireless Apple CarPlay and Android Auto. An 11-inch digital driver display provides vehicle information. Over 15 standard safety features include enhanced automatic emergency braking, blind zone alert, adaptive cruise control, and lane keep assist with lane departure warning.

2026 GMC Acadia AT4

The Acadia AT4 brings three-row seating and off-road capability in a midsize SUV package. This 7-passenger model features AWD and a turbocharged engine.

Powertrain and Performance

A 2.5L turbocharged 4-cylinder engine delivers 328 horsepower and 326 lb-ft of torque through an 8-speed automatic transmission. Active Torque Control AWD manages power distribution across surfaces. Maximum trailering capacity reaches 2,268 kg (5,000 lb).

Key specifications:

• Engine: 2.5L Turbo 4-cylinder
• Power: 328 hp
• Torque: 326 lb-ft
• Transmission: 8-speed automatic
• Drivetrain: AWD (Active Torque Control)
• Max Trailering: 2,268 kg (5,000 lb)

Off-Road Equipment

The Acadia AT4 features a lifted suspension with off-road tuning. Front and underbody skid plates protect components during trail driving. 18-inch dark machined aluminum wheels mount all-terrain tires. Red recovery hooks and gloss-black roof rails complete the exterior package.

Cargo Capacity:

• Behind 3rd row: 651 L
• Behind 2nd row: 1,622 L
• Behind 1st row: 2,760 L

Interior and Technology

The AT4-exclusive Forest Storm interior theme includes Mahogany accents and Night Rider chrome. AT4 stitching appears on head restraints, with AT4-embossed sill plates at door openings. A 15-inch Premium GMC Infotainment System includes Google built-in compatibility and voice-activated technology. The Bose Premium 12-speaker system with subwoofer delivers audio throughout three rows.

Up to seven drive modes allow drivers to optimize vehicle performance based on conditions. Terrain Mode specifically addresses off-road driving scenarios. Nine available camera views include HD Surround Vision and Rear Camera Mirror for enhanced visibility.

Which AT4 Model Fits Your Needs?

For midsize truck versatility: Canyon AT4 delivers off-road capability in a manageable size for Mississauga streets and Ontario trails. The AT4X extends capability for drivers who regularly tackle challenging terrain.

For full-size truck capability: Sierra 1500 AT4 provides diesel efficiency or V8 power with off-road suspension. The AT4X adds advanced dampers and locking differentials for maximum traction control.

For electric truck innovation: Sierra EV AT4 pairs zero-emission driving with off-road features including 4-Wheel Steer and specialized Terrain Mode.

For heavy-duty work: Sierra HD AT4 handles serious towing and payload requirements with off-road capability. The AT4X delivers additional ground clearance and specialized suspension for extreme conditions.

For compact SUV efficiency: Terrain AT4 brings off-road features to a fuel-efficient package suitable for daily driving and weekend adventures.

For three-row capability: Acadia AT4 pairs 7-passenger seating with off-road suspension and all-terrain tires for family-focused adventure driving.

Experience the AT4 Lineup at Applewood Chevrolet Buick GMC

The 2026 GMC AT4 lineup provides six distinct approaches to off-road capability and rugged performance. From the compact Terrain AT4 to the heavy-duty Sierra HD AT4X, each model delivers specialized engineering for specific driving requirements. Visit Applewood Chevrolet Buick GMC in Mississauga to explore the complete AT4 range and identify which model aligns with your driving needs in Ontario.

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