The 2026 GMC Sierra 3500HD AT4 Crew Cab Standard Box 4-Wheel Drive combines heavy-duty diesel power, rugged off-road engineering, and premium interior refinement in a commanding, adventure-ready truck. Finished in bold Onyx Black with a distinctive Jet Black and Kalahari interior, this Sierra HD AT4 is built for demanding workloads, serious towing, and off-road exploration, delivering professional-grade strength with exceptional comfort and advanced technology. 

Performance & Capability 

Engine: 6.6L Duramax Turbo-Diesel V8 engineered for exceptional torque and heavy-duty performance 

Transmission: 10-speed automatic for smooth, controlled power delivery under demanding conditions 

Drivetrain: 4-Wheel Drive with Autotrac two-speed transfer case for confident traction across changing terrain 

Rear Axle: 3.42 ratio designed to support strong pulling performance and balanced drivability 

Off-Road Suspension: AT4 off-road suspension package built to handle rugged trails and challenging terrain 

Rear Differential: Automatic locking rear differential for enhanced traction when conditions get tough 

Engine Braking: Integrated exhaust brake for added control on steep descents and while towing 

Trailering Technology: Integrated trailer brake controller, Hitch View, trailering app, and provisions for trailer cameras 

Heavy-Duty Cooling: Engine oil and transmission oil coolers to support demanding driving and towing conditions 

Gooseneck & 5th-Wheel Prep: Factory-installed preparation for compatible heavy-duty trailer setups 

 

Winter & All-Season Comfort 

Heated and ventilated front seats for year-round comfort 

Heated rear outboard seats and heated steering wheel for chilly Canadian mornings 

Remote Start System to help prepare the cabin before departure 

Engine block heater for easier cold-weather starts 

Dual-zone automatic climate control with rear air vents 

Rain-sensing windshield wipers and rear-window defogger for changing weather 

Winter grille cover and premium floor liners for added cold-weather practicality 

 

Interior Comfort & Convenience 

Premium Jet Black and Kalahari interior with distinctive AT4 accents 

Power-adjustable front bucket seats with driver memory settings 

Power sliding rear window and spacious Crew Cab seating 

Power sunroof for added natural light and fresh air 

13.4-inch GMC Premium Infotainment touchscreen with Google built-in compatibility 

12-inch configurable digital driver display for essential vehicle information 

Multicolour 15-inch Head-Up Display that projects key driving information into the drivers view 

Bose premium audio system for an immersive listening experience 

Wireless phone projection, wireless charging, and multiple USB ports 

Heated, power-adjustable trailering mirrors with auto-dimming functionality 

120V power outlets in the cabin and truck bed for tools and compatible devices 

Rear-seat storage package for convenient organization 

 

Safety & Driver Assistance 

Sierra HD Pro Safety technologies for added confidence behind the wheel 

Adaptive Cruise Control and Following Distance Indicator for supported highway driving 

Forward Collision Alert with Automatic Emergency Braking 

Front Pedestrian Braking and Lane Departure Warning 

Rear Cross Traffic Alert and Trailer Side Blind Zone Alert 

HD Surround Vision for enhanced visibility when maneuvering 

Front and Rear Park Assist for easier parking and low-speed navigation 

Rear Camera Mirror and Bed View Camera for improved visibility around the truck and cargo 

Drivers Safety Alert Seat, Teen Driver technology, and Buckle-to-Drive features 

 

Exterior Styling & Utility 

Exterior Colour: Sterling Metallix a glossy finish that emphasizes the AT4s bold presence 

Wheels: 20-inch black aluminum wheels paired with all-terrain tires 

Lighting: LED headlamps, front LED fog lamps, LED cargo bed lighting, and roof marker lamps 

Signature AT4 styling with red front recovery hooks and rugged body accents 

GMC MultiPro Tailgate with multiple configurations for easier loading and bed access 

Spray-on bedliner and rear wheelhouse liners for added cargo-box protection 

Off-road high-clearance assist steps for convenient entry and exit 

Bed-mounted 120V power outlet for worksite and outdoor convenience 

Rear bumper corner steps for easier access to the truck bed 

Perimeter lighting and task lighting integrated into the exterior mirrors 

Whether youre hauling heavy equipment, towing a fifth-wheel trailer, tackling remote backroads, or navigating harsh winter conditions, the 2026 GMC Sierra 3500HD AT4 delivers formidable diesel strength, serious heavy-duty capability, and premium everyday comfort. With its rugged off-road design, advanced trailering technology, and luxurious AT4 interior, this truck is built to take on demanding challenges with confidence, control, and unmistakable GMC presence. 

 



AMVIC Licensed Dealer

*Every reasonable effort is made to ensure the accuracy of the information shown. The Standard Equipment listed is provided at the time of the manufacture and may not match the exact vehicle displayed. Please confirm with a sales representative the accuracy of this information.

Engine: 8 Cylinder Engine 6.6L
Safety EquipmentStabiliTrak, stability control system with Proactive Roll Avoidance and traction control includes electronic trailer sway control and hill start assistAirbags, Dual-stage frontal airbags for driver and front outboard passenger; Seat-mounted side-impact airbags for driver and front outboard passenger; Head-curtain airbags for front and rear outboard seating positions; Includes front outboard Passenger Sensing System for frontal outboard passenger airbagFront and Rear Park Assist, ultrasonicRear Cross Traffic AlertTeen Driver a configurable feature that lets you activate customizable vehicle settings associated with a key fob, to help encourage safe driving behaviour. It can limit certain available vehicle features, and it prevents certain safety systems from being turned off. An in-vehicle report card gives you information on driving habits and helps you to continue to coach your new driverRear Seat ReminderHitch Guidance dynamic single line to aid in truck trailer alignment for hitchingSafety Alert SeatHill Descent ControlTrailer Side Blind Zone AlertTire Pressure Monitoring System auto learn, includes Tire Fill Alert (does not apply to spare tire)Hitch Guidance with Hitch View with image adjustment, Pan/Zoom/TiltFront Pedestrian Braking (Included and only available with (PDI) Sierra HD Pro Safety.)Automatic Emergency Braking (Included and only available with (PDI) Sierra HD Pro Safety.)LED Signature DRL'sHD Surround Vision provides the driver with an overhead view of the scene around the vehicle on a centre stack display. Includes front camera washer.Trailer Camera Provisions and trailer viewing softwareForward Collision Alert (Included and only available with (PDI) Sierra HD Pro Safety.)Following Distance Indicator (Included and only available with (PDI) Sierra HD Pro Safety.)Lane Departure Warning (Included and only available with (PDI) Sierra HD Pro Safety.)Seat Belt Adjustable Guide Loops, front row onlyRear Seat Belt Indicator (Requires Crew Cab or Double Cab model.)OnStar Services capable (See onstar.ca for details and limitations. Services vary by model. Service plan required.)Daytime Running Lamps LED signature lightingBed View Camera camera in the CHMSL to show a view of the cargo bed, display located in infotainment screen, includes Two Trailer Camera ProvisionsBuckle to Drive prevents vehicle from being shifted out of Park until driver seat belt is fastened; times out after 20 seconds and encourages seat belt use (Included and only available with (PDI) Sierra HD Pro Safety)OnStar Basics (OnStar Fleet Basics for Fleet) Drive more confidently with up to 8 years of core OnStar services including mobile app commands, connectivity for select apps that provide in-vehicle voice assistance and navigation with real-time traffic, and Automatic Crash Response. (Requires (UE1) OnStar. OnStar Basics includes access to remote commands through your vehicle's mobile app (compatible smartphone required); Automatic Crash Response (not all vehicles may transmit all crash data; OnStar links to emergency services); and wireless connectivity for select apps that provide in-vehicle voice assistance and navigation with real-time traffic (Voice & Maps apps are subject to change at any time and may be provided by third parties). Term begins from date of vehicle delivery. Paid subscription required after expiry. Services are dependent on compatible wireless networks provided by third-party wireless service providers, working vehicle electrical systems, GPS signal and other factors outside GM control. Changes in technology and wireless networks may limit or prevent the operation of certain services. For customers who also separately receive or purchase a Premium Plan or Vehicle Data Plan to use Wi-Fi Hotspot and In-Vehicle Apps, the data provided as part of that plan will also be used by any Voice & Maps apps which already had data connectivity under this Basics plan; if any applicable data caps are reached, Voice & Maps apps will continue to function for the duration of this Basics plan but additional vehicle data plan(s) must be purchased to use Wi-Fi Hotspot and In-Vehicle Apps. Services, connectivity, and capabilities have additional terms and limitations and are subject to change, and will vary by model, vehicle configuration, conditions, and geographical and technical restrictions. Non-refundable and no cash value. See onstar.ca for details.)Interior EquipmentSeat adjuster, driver 10-way power including lumbarSeat adjuster, passenger 10-way power including lumbarSeating, heated driver and front outboard passengerSeats, ventilated driver and front passengerSeats, heated second row outboard seatsDriver memory, recalls driver "presets" for power driver seat and outside mirrorsCentre Console, floor-mounted with cup holders, cell phone storage, power cord management, hanging file folder capabilityFloor covering, colour-keyed carpetingSteering wheel, heatedSteering wheel audio controlsExterior Temperature Display located in radio displayCompass, located in instrument clusterWindow, power front, drivers express up/downWindow, power front, passenger express up/downWindows, power rear, express downDoor locks, powerRemote vehicle starter systemTheft-deterrent system, unauthorized entryPower outlet, instrument panel, 120-volt (400 watts shared with (KC9) bed mounted power outlet)Power outlet, bed mounted, 120-volt (400 watts shared with (KI4) instrument panel mounted power outlet)Defogger, rear-window electricMirror, inside rearview auto-dimmingAir conditioning, dual-zone automatic climate controlSteering column, manual Tilt-Wheel and telescopingAdaptive Cruise ControlSteering wheel, wrappedWireless ChargingUSB Ports, 2 (first row) located on consoleAir vents, rearDriver Information Centre, enhanced, 12.3" diagonal reconfigurable multicolour digital displayAssist handles, front A-pillar mounted for driver and passenger, rear B-pillar mountedSeats, front bucket with centre consolePremium Floor Liners with removable carpet insert, frontPremium Floor Liners with removable carpet insert, rearGMC Premium information Display- 13.4" diagonal Multicolour touch screenKeyless Open and Start includes remote keyless entryUSB ports, (2) charge-only, rearSeat, Up-level Rear with Storage Package, 60/40 folding bench for Crew Cab models includes full-length bench seat, seatback storage on left and right side, centre fold out armrest with 2 cupholders, full cab width underseat storage, (includes child seat top tether anchor)In-Vehicle Trailering App System, includes checklist, trailer maintenance reminders, trailer security alerts, trailer mileage, tow/haul reminder, trailer electrical diagnostics and Trailer Tire Pressure Monitor System module (Includes trailer tire pressure monitoring alert when (PTT) trailer tire pressure monitor sensors are installed.)Seat trim, Perforated Front Leather seating surfacesUSB ports, 2, Charge/Data ports located inside centre consoleExterior EquipmentSingle Rear WheelsTire carrier lock keyed cylinder lock that utilizes same key as ignition and doorCornerStep, rear bumperMirrors, outside power-adjustable vertical trailering with heated and auto-dimming upper glass, (driver and passenger) lower convex mirrors, turn signal indicators, puddle lamps, perimeter lighting, auxiliary lighting, power folding/extending (extends 3.31" [84.25mm])Glass, deep-tintedTailgate and bed rail protection caps, topDoor handles, body-colourMouldings, beltline, BlackLamps, cargo area, cab mounted integrated with centre high mount stop lamp, with switch in bank on left side of steering wheelMirror caps, high gloss BlackWheelhouse liners, rearWipers, front rain-sensingFog lamps, LEDBed Step, Black integrated on forward portion of bed on driver and passenger sideTire, spare LT275/70R18 all-terrain, blackwallBumper, front, body-colour lowerBumper, rear body-colour with bumper CornerStepsIntelliBeam, automatic high beam on/off (Included and only available with (PDI) Sierra HD Pro Safety.)LED Cargo Area Lighting located in cargo bed activated with switch on centre switch bank or key fobTaillamps, Animated LED Signature Tail, Stop, turn and Reverse lampsTailgate, gate function manual with EZ Lift includes power lock and release, includes hitch area lightHeadlamps, Animated LED projectors, LED turn signals and Daytime Running LampsTires, LT275/65R20 all-terrain, blackwall (Requires single rear wheels.)Tailgate, GMC MultiPro Tailgate with six functional load/access features. NOTE: Auto release can be disabled if ball hitch is installed. See Owner's manual for detailsWheels, 20" (50.8 cm) High Gloss black aluminum wheels, 8 spokesCargo tie downs (12), fixed, rated at 500 lbs per cornerGrille, Gloss Black header and grille insert bars with Black chrome accentsBedliner, Spray-on Pickup bedliner with GMC logo (does not include spray-on liner on tailgate due to Black composite inner panel)Entertainment EquipmentBose Sound System, premium 7-speaker system with Richbass wooferBluetooth for phone connectivity to vehicle infotainment systemWireless phone projection for Apple CarPlay and Android AutoAudio System, 13.4" diagonal Premium GMC Infotainment System with Google built in apps such as navigation and voice assistance, includes colour touch-screen, multi-touch display, AM/FM stereo, Bluetooth streaming audio for music and most phones; featuring wireless Android Auto and Apple CarPlay capability for compatible phones.Wi-Fi Hotspot capable (Terms and limitations apply. See onstar.com or dealer for details.)SiriusXM Trial SubscriptionSiriusXM with 360L Trial Subscription. SiriusXM with 360L transforms your customers' ride with our most extensive and personalized radio experience on the road. (IMPORTANT: The SiriusXM trial subscription is not provided on vehicles that are ordered for Fleet Daily Rental ("FDR") use. Certain features and/or content may not be available unless an active data connection is enabled in the vehicle. Content varies by SiriusXM subscription plan. Features and display may vary by vehicle. All SiriusXM services require a subscription, sold separately by SiriusXM after the trial period. Your SiriusXM service will automatically stop at the end of your trial unless you decide to subscribe. If you decide to continue service after your trial, the subscription plan you choose will continue for an indeterminate term and you will be charged according to your chosen payment method at the then-current rates unless and until you cancel. Taxes apply. Please see the SiriusXM Customer Agreement at siriusxm.ca/terms for complete terms and how to cancel, which includes calling SiriusXM at 1-888-539-7474. All rates, content, and programming are subject to change. SiriusXM uses personal information in accordance with SiriusXM Privacy Policy, available at siriusxm.ca/privacy. SiriusXM Canada Inc. "SiriusXM", the SiriusXM logo, channel names and logos are trademarks of Sirius XM Radio Inc. and are used under license.)Mechanical EquipmentEngine, 6.6L V8 with Direct Injection and Variable Valve Timing, gasoline (401 hp [299 kW] @ 5200 rpm, 464 lb-ft of torque [629 N-m] @ 4000 rpm)Air filtration monitoringTransfer case, two-speed active electronic Autotrac with push button controlFour wheel driveCooling, external engine oil coolerCooling, auxiliary external transmission oil coolerBattery, heavy-duty 720 cold-cranking amps/80 Amp-hr maintenance-free with rundown protection and retained accessory power (Included and only available with (L8T) 6.6L V8 gas engine.)Alternator, 170 amps (Requires (L8T) 6.6L V8 gas engine.)Trailer brake controller, integratedFrame, fully-boxed, hydroformed front section and a fully-boxed stamped rear sectionBrakes, 4-wheel antilock, 4-wheel disc with DURALIFE rotorsBrake lining wear indicatorRear axle, 3.73 ratio (Requires (L8T) 6.6L V8 gas engine.)Pickup bed includes bed assist stepPush Button StartAir filter, heavy-dutyAuto-locking rear differentialRecovery hooks, RedSkid Plates protect the oil pan, front axle and transfer caseSuspension, Off-Road includes twin-tube shocksCapless Fuel Fill (Requires (L8T) 6.6L gas V8 engine.)GVWR, 11,700 lbs. (5307 kg) with single rear wheels (Included and only available with model TK30943 model and (L8T) 6.6L V8 gas engine. Requires single rear wheels.)GVWR, 11,550 lbs. (5239 kg) with single rear wheels (Included and only available with TK30743 model and (L8T) 6.6L V8 gas engine. Requires single rear wheels.)Steering, Digital Variable Steering Assist This system automatically adjusts steering based on speed, road conditions, and other inputs to reduce driver effort and fatigueTransmission, 10-Speed automaticOther EquipmentTrailering Package includes trailer hitch, 7-pin and 4-pin connectors and (CTT) Hitch GuidanceX31 Off-Road Package includes (JHD) Hill Descent Control, (NZZ) skid plates, Off-Road suspension and Twin-tube Rancho shocksSierra HD Pro Safety includes (UEU) Forward Collision Alert, (UE4) Following Distance Indicator, (UKJ) Front Pedestrian Braking, (TQ5) IntelliBeam, (UFL) Lane Departure Warning, (T8Z) Buckle to Drive and (UHY) Automatic Emergency BrakingProGrade Trailering System includes (PZ8) Hitch Guidance with Hitch View and (UET) In-vehicle Trailering App