Vehicle Details
Body Style
Truck
Engine
6.6L 8Cyl
Exterior Colour
White
Interior Colour
Black
Transmission
Automatic
Drivetrain
4×4
Stock
303888
Fuel Type
Diesel
Trim Details
Crew Cab Standard Box 4-Wheel Drive AT4X
Description
The 2026 GMC Sierra 2500HD AT4X combines heavy-duty diesel power, premium luxury, and extreme off-road capability into one uncompromising package. Engineered for serious work and built to conquer challenging terrain, this AT4X delivers rugged confidence, advanced technology, and upscale comfort for drivers who demand the very best from their truck.Â
Performance & CapabilityÂ
Engine: Duramax® 6.6L V8 Turbo-Diesel delivering exceptional torque, towing capability, and long-haul efficiencyÂ
Transmission: Allison®-inspired 10-speed automatic transmission engineered for smooth, responsive performance under heavy loadsÂ
Drivetrain: Autotrac® Two-Speed 4-Wheel Drive system for superior traction in changing conditionsÂ
Off-Road Suspension: AT4X-specific off-road suspension package designed for enhanced control and confidence on rugged terrainÂ
Rear Differential: Electronic locking rear differential for maximum traction when conditions get challengingÂ
Hill Descent Control for controlled and confident downhill performanceÂ
Heavy-Duty Cooling Systems including engine oil cooler, transmission oil cooler, and heavy-duty air filtrationÂ
Exhaust Brake System for enhanced control and confidence while towing or descending steep gradesÂ
Trailering Equipment: Integrated trailer brake controller, hitch guidance, Hitch View, trailer camera provisions, and advanced trailering technologiesÂ
Gooseneck/5th-Wheel Prep Package for serious towing capabilityÂ
Winter & Weather ComfortÂ
Heated & Ventilated Front Seats providing year-round comfortÂ
Heated Rear Outboard Seats for premium second-row passenger comfortÂ
Heated Steering Wheel for cold-weather driving convenienceÂ
Remote Start System to warm up or cool down the cabin before departureÂ
Dual-Zone Automatic Climate Control for personalized comfort settingsÂ
Engine Block Heater for dependable cold-weather startsÂ
Rain-Sensing Windshield Wipers automatically adapt to changing weather conditionsÂ
Winter Grille Cover designed to help optimize cold-weather operationÂ
Interior Comfort & ConvenienceÂ
Premium Leather-Appointed AT4X Interior with distinctive Obsidian Rush accentsÂ
Front Bucket Seats featuring power adjustment, lumbar support, power bolsters, and massage functionality for both driver and passengerÂ
Memory Settings for driver preferences and mirror positioningÂ
Power Sliding Rear Window and Rear Seat Storage Package for added practicalityÂ
Wireless Charging Pad and multiple USB/120V power outlets throughout the cabinÂ
Keyless Open & Push-Button Start for seamless access and operationÂ
Power Sunroof bringing additional light and openness to the cabinÂ
Rear Camera Mirror for an expanded view behind the vehicleÂ
Wireless Apple CarPlay® & Android Autoâ„¢ compatibility for effortless smartphone integrationÂ
13.4" GMC Premium Infotainment Touchscreen with Google Built-In capabilityÂ
12" Digital Driver Information Centre with customizable vehicle information displaysÂ
Bose® Premium Audio System delivering rich, immersive sound qualityÂ
Head-Up Display projecting key driving information directly onto the windshieldÂ
Safety & Driver AssistanceÂ
Sierra HD Pro Safety Suite for enhanced confidence behind the wheelÂ
Forward Collision Alert with Automatic Emergency BrakingÂ
Front Pedestrian Braking for added awareness in busy environmentsÂ
Lane Departure Warning to help maintain lane positionÂ
Adaptive Cruise Control for relaxed highway travelÂ
HD Surround Vision providing a comprehensive view around the truckÂ
Front & Rear Park Assist for easier maneuvering in tight spacesÂ
Rear Cross Traffic Alert for enhanced awareness while reversingÂ
Trailer Side Blind Zone Alert for added confidence when towingÂ
Following Distance Indicator and Driver Safety Alert SeatÂ
Teen Driver Technology and Buckle-to-Drive functionalityÂ
Exterior Styling & UtilityÂ
Exterior Colour: Summit White — clean, bold, and unmistakably GMCÂ
18" Aluminum Wheels wrapped in aggressive LT305/70R18 Mud-Terrain TiresÂ
Signature LED Headlamps, LED Fog Lamps, Roof Marker Lamps, and LED Cargo Bed LightingÂ
Power-Retractable Black Assist Steps with integrated LED lightingÂ
GMC MultiPro Tailgate offering multiple loading and utility configurationsÂ
MultiPro Tailgate Audio System by Kicker® for enhanced outdoor entertainmentÂ
Spray-On Bedliner protecting the cargo box from daily wear and tearÂ
Bed-Mounted 120V Power Outlet for added worksite functionalityÂ
Power Locking EZ Lift Tailgate for effortless accessÂ
Red Front Recovery Hooks highlighting the AT4X's serious off-road intentÂ
Heated Power Trailer Mirrors with Auto-Dimming functionalityÂ
Deep-Tinted Glass, black exterior accents, and aggressive AT4X styling create a commanding presence wherever the road, or trail, leadsÂ
Whether you're towing heavy equipment, exploring remote backcountry trails, or enjoying premium everyday comfort, the 2026 GMC Sierra 2500HD AT4X delivers exceptional diesel capability, advanced technology, and uncompromising off-road performance. It's the ultimate heavy-duty truck for drivers who refuse to choose between luxury, strength, and adventure.Â
Â
Packages & Options
Standard Equipment
Technical Specifications
-
AM/FM Stereo
-
Auxiliary Audio Input
-
Bluetooth Connection
-
MP3 Player
-
Navigation System
-
Smart Device Integration
-
Requires Subscription
-
Satellite Radio
-
Premium Sound System
-
WiFi Hotspot
-
Aluminum Wheels
-
Tires - Front All-Season
-
Tires - Rear All-Season
-
Conventional Spare Tire
-
Generic Sun/Moonroof
-
Sun/Moonroof
-
Bumper, front, body-colour lower (Bumper color will be High Gloss Black.)
-
Bumper, rear body-colour with bumper CornerSteps (Bumper color will be High Gloss Black.)
-
Power Retractable Running Boards
-
Running Boards/Side Steps
-
Bed Liner
-
Bed Step, Black integrated on forward portion of bed on driver and passenger side
-
CornerStep, rear bumper (Not available with (ULV) AT4X AEV Edition.)
-
Cargo tie downs (12), fixed, rated at 500 lbs (226.8 kg) per corner
-
Wheelhouse liners, rear
-
Mouldings, beltline, Black
-
Grille (Gloss Black header and grille insert bars with Dark Nickel inserts.)
-
Daytime Running Lights
-
Automatic Highbeams
-
Fog Lamps
-
Lamps, cargo area cab mounted integrated with centre high mount stop lamp, with switch in bank on left side of steering wheel
-
LED Cargo Area Lighting located in cargo bed activated with switch on centre switch bank or key fob
-
Taillamps, Animated LED Signature Tail, Stop, turn and Reverse lamps
-
Lamps, Smoked Amber roof marker, (LED)
-
Heated Mirrors
-
Integrated Turn Signal Mirrors
-
Power Folding Mirrors
-
Power Mirror(s)
-
Mirror caps, high gloss Black
-
Privacy Glass
-
Intermittent Wipers
-
Rain Sensing Wipers
-
Variable Speed Intermittent Wipers
-
Door handles, body-colour (With (ULV) AT4X AEV Edition door handles will be Gloss black.)
-
Integrated Tailgate Step
-
Tailgate, gate function manual with EZ Lift includes power lock and release, includes hitch area light
-
Tailgate and bed rail protection caps, top
-
Bucket Seats
-
Leather Seats
-
Pass-Through Rear Seat
-
Rear Bench Seat
-
Driver Adjustable Lumbar
-
Power Driver Seat
-
Seat-Massage
-
Passenger Adjustable Lumbar
-
Power Passenger Seat
-
Heated Front Seat(s)
-
Cooled Front Seat(s)
-
Heated Rear Seat(s)
-
Mirror Memory
-
Seat Memory
-
Floor covering, colour-keyed carpeting
-
Floor Mats
-
Leather Steering Wheel
-
Heated Steering Wheel
-
Steering Wheel Audio Controls
-
Adjustable Steering Wheel
-
Driver Information Centre, enhanced, 12.3" diagonal reconfigurable multicolour digital display
-
Heads-Up Display
-
Rear Seat Reminder
-
GMC Premium information Display- 13.4" diagonal Multicolour touch screen
-
Exterior Temperature Display, located in radio display
-
Compass, located in instrument cluster
-
Power Windows
-
Rear Defrost
-
Sliding Rear Window
-
Power Door Locks
-
Keyless Entry
-
Keyless Start
-
Remote Engine Start
-
Adaptive Cruise Control
-
Cruise Control
-
Universal Garage Door Opener
-
Wireless Charging
-
Security System
-
Power outlet, instrument panel, 120-volt (400 watts shared with (KC9) bed mounted power outlet)
-
Auxiliary Audio Input
-
MP3 Player
-
USB ports, (2) charge-only, rear
-
Air vents, rear
-
A/C
-
Climate Control
-
Multi-Zone A/C
-
Auto-Dimming Rearview Mirror
-
Back-Up Camera
-
Assist handles front A-pillar mounted for driver and passenger, rear B-pillar mounted
-
8 Cylinder Engine
-
Gasoline Fuel
-
10-Speed A/T
-
A/T
-
Rear axle, 3.73 ratio (Requires (L8T) 6.6L V8 gas engine.)
-
Running Boards/Side Steps
-
GVWR, 11,025 lbs. (5001 kg) (Included and only available with TK20743 model and (L8T) 6.6L V8 gas engine with 18", 20" or 22" wheels.)
-
Keyless Start
-
Hill Descent Control
-
Transfer case, two-speed active, electronic Autotrac with push button control
-
Locking/Limited Slip Differential
-
Four Wheel Drive
-
Cooling, external engine oil cooler
-
Cooling, auxiliary external transmission oil cooler
-
Air filter, heavy-duty
-
Air filtration monitoring
-
Battery, 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, integrated
-
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.)
-
Tow Hooks
-
Skid Plates, front aluminum
-
Skid Plates, Transfer case, steel
-
Frame, fully-boxed, hydroformed front section and a fully-boxed stamped rear section
-
Suspension, Off-Road Includes, 1.5" suspension lift: front suspension lift composed of: Control Arms, Ball Joints, Knuckles, DSSV Dampers, rear suspension lift composed of spacer block and DSSV Dampers and Half shafts w/ revised joints, 3-stage Leaf springs from 3500
-
Power Steering
-
4-Wheel Disc Brakes
-
ABS
-
Brake lining wear indicator
-
Capless Fuel Fill (Requires (L8T) 6.6L gas V8 engine.)
-
Automatic Highbeams
-
Front Collision Mitigation
-
Front Collision Warning
-
Lane Departure Warning
-
Tow Hitch
-
ProGrade Trailering System includes (PZ8) Hitch Guidance with Hitch View and (UET) In-vehicle Trailering App
-
Front Collision Mitigation
-
Front Collision Warning
-
Stability Control
-
Traction Control
-
Daytime Running Lights
-
Driver Air Bag
-
Front Head Air Bag
-
Front Side Air Bag
-
Passenger Air Bag
-
Passenger Air Bag Sensor
-
Rear Head Air Bag
-
Requires Subscription
-
Telematics
-
Rear Parking Aid
-
Aerial View Display System
-
Back-Up Camera
-
Bed View Camera, camera in the CHMSL to show a view of the cargo bed display located in infotainment screen, includes Two Trailer Camera Provisions
-
Trailer Camera Provisions and trailer viewing software
-
Hitch Guidance dynamic single line to aid in truck trailer alignment for hitching
-
Lane Departure Warning
-
Rear Seat Belt Indicator
-
Cross-Traffic Alert
-
Blind Spot Monitor
-
Seat Belt Adjustable Guide Loops, front row only
-
Buckle 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.)
-
Safety Alert Seat
-
Driver Restriction Features
-
Tire Pressure Monitor
-
Trailer Tire Pressure Monitor Sensors includes set of 4 sensors. Sensor functionality requires (UET) In-Vehicle Trailering App to be ordered with the vehicle and installed by the factory. Sensors will be shipped loose with the truck and will need to be installed on trailer by customer. System is capable of monitoring up to 6 wheels. Additional or replacement sensors are available through GM Accessories
-
Trailering Information Label provides max trailer ratings for tongue weight, conventional, gooseneck and 5th wheel trailering
No matches were found.
-
Vehicle NameGMC Sierra 2500HD
-
Body StyleCrew Cab Pickup
-
Body CodeE63
-
DrivetrainFour Wheel Drive
-
Trans Order CodeMGM
-
Trans Type10
-
Trans Description Cont.Automatic
-
First Gear Ratio (:1)4.54
-
Second Gear Ratio (:1)2.87
-
Third Gear Ratio (:1)2.06
-
Fourth Gear Ratio (:1)1.72
-
Fifth Gear Ratio (:1)1.48
-
Sixth Gear Ratio (:1)1.26
-
Seventh Gear Ratio (:1)1.00
-
Eighth Gear Ratio (:1)0.85
-
Ninth Gear Ratio (:1)0.69
-
Tenth Gear Ratio (:1)0.63
-
Reverse Ratio (:1)4.54
-
Transfer Case Gear Ratio (:1), High1
-
Passenger Capacity5
-
Front Head Room (in)39.88
-
Front Leg Room (in)44.53
-
Front Shoulder Room (in)66.02
-
Front Hip Room (in)61.18
-
Second Head Room (in)40.12
-
Second Leg Room (in)43.4
-
Second Shoulder Room (in)65.3
-
Second Hip Room (in)60.24
-
Gross Axle Wt Rating - Front (lbs)5600
-
Gross Axle Wt Rating - Rear (lbs)6600
-
Curb Weight - Front (lbs)4013
-
Curb Weight - Rear (lbs)2812
-
Gross Vehicle Weight Rating Cap (lbs)11350
-
Gross Combined Wt Rating (lbs)27500
-
Dead Weight Hitch - Max Trailer Wt. (lbs)5000
-
Dead Weight Hitch - Max Tongue Wt. (lbs)500
-
Wt Distributing Hitch - Max Trailer Wt. (lbs)18500
-
Wt Distributing Hitch - Max Tongue Wt. (lbs)1850
-
Fifth Wheel Hitch - Max Trailer Wt. (lbs)17300
-
Fifth Wheel Hitch - Max Tongue Wt. (lbs)4325
-
Maximum Trailering Capacity (lbs)18500
-
Engine Order CodeL5P
-
Engine TypeTurbocharged Diesel V8
-
Displacement6.6L
-
Fuel SystemDirect Injection
-
SAE Net Horsepower @ RPM470 @ 2800
-
SAE Net Torque @ RPM975 @ 1600
-
Engine Oil CoolerYes
-
Cold Cranking Amps @ 0° F (Primary)720
-
Maximum Alternator Capacity (amps)220
-
Frame TypeBox Ladder
-
Suspension Type - FrontTorsion Bar
-
Suspension Type - Rear3-Stage Multi-Leaf
-
Axle Ratio (:1) - Front3.42
-
Axle Ratio (:1) - Rear3.42
-
Shock Absorber Diameter - Front (mm)55
-
Shock Absorber Diameter - Rear (mm)51
-
Stabilizer Bar Diameter - Front (in)1.38
-
Front Tire Order CodeQMG
-
Rear Tire Order CodeQMG
-
Spare Tire Order CodeQNZ
-
Front Tire SizeLT305/70R18
-
Rear Tire SizeLT305/70R18
-
Spare Tire SizeLT305/70R18
-
Front Wheel Size (in)18
-
Rear Wheel Size (in)18
-
Spare Wheel Size (in)18
-
Front Wheel MaterialAluminum
-
Rear Wheel MaterialAluminum
-
Steering TypePwr Recirculating Ball
-
Turning Diameter - Curb to Curb (ft)51.8
-
Brake TypePwr
-
Brake ABS System4-Wheel
-
Disc - FrontYes
-
Disc - RearYes
-
Front Brake Rotor Diam x Thickness (in)14 x 1.6
-
Rear Brake Rotor Diam x Thickness (in)14.1 x 1.3
-
Fuel Tank Capacity, Approx (L)136
-
Wheelbase (in)159
-
Length, Overall (in)250.75
-
Width, Max w/o mirrors (in)81.85
-
Height, Overall (in)82.68
-
Cab to Axle (in)42.36
-
Ground Clearance, Front (in)11.61
-
Ground Clearance, Rear (in)11.61
-
Cargo Box Length @ Floor (in)82.2
-
Cargo Box Width @ Floor (in)71.4
-
Cargo Box Width @ Wheelhousings (in)51.85
-
Cargo Box (Area) Height (in)21
-
Cargo Volume (ft³)69.5
No matches were found.
Similar Vehicles
Crew Cab Standard Box 4-Wheel Drive AT4X
VIN: 1GT4UZEY5TF312356
In-Transit
4WD Crew Cab Long Box SLE
VIN: 1GT4UTEY1TF262732
Crew Cab Short Box 4-Wheel Drive Denali Ultimate
VIN: 1GTUUHEL2TZ354979
City: 16L/100 km • Hwy: 12.1L/100 km
4WD Crew Cab Standard Box Denali
VIN: 1GT4UWEY1TF264241
* Every reasonable effort is made to ensure the accuracy of the information listed above. Vehicle pricing, incentives, options (including standard equipment), and technical specifications listed is for the 2026 GMC Sierra 2500HD AT4X may not match the exact vehicle displayed. Please confirm the accuracy of this information with a sales representative.
Calculate Payments
Finance
Lease