Vehicle Details
Body Style
Truck
Engine
6.6L 8Cyl
Exterior Colour
White
Interior Colour
Black
Transmission
Automatic
Drivetrain
4×4
Stock
303729
Fuel Type
Diesel
Trim Details
4WD Crew Cab Standard Box AT4
Description
The 2026 GMC Sierra 3500HD AT4 Crew Cab Standard Box combines heavy-duty diesel strength, premium comfort, and advanced trailering technology into one commanding off-road-ready truck. Designed for serious towing, rugged adventures, and everyday refinement, this Sierra HD AT4 delivers professional-grade capability with bold styling and upscale craftsmanship. Â
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Performance & Capability Â
Engine: Duramax® 6.6L V8 Turbo-Diesel delivering exceptional torque, towing confidence, and heavy-duty performance Â
Transmission: Allison® 10-speed automatic transmission engineered for smooth power delivery and optimized hauling capability Â
Drivetrain: 4-Wheel Drive (4WD) with Autotrac® two-speed transfer case for enhanced traction in challenging conditions Â
Off-Road Suspension Package tuned for rugged terrain and confident trail performance Â
Automatic Locking Rear Differential for improved traction on loose or uneven surfaces Â
Hill Descent Control for controlled downhill driving on steep grades Â
Engine Exhaust Brake for added control and confidence while towing or descending hills Â
Heavy-Duty Cooling Systems including engine oil cooler and transmission oil coolerÂ
Gooseneck/5th Wheel Prep Package for advanced towing versatility Â
Integrated Trailer Brake Controller, Hitch Guidance with Hitch View, and In-Vehicle Trailering App for easier towing management Â
Trailer Camera Provisions and Bed View Camera for enhanced visibility while trailering Â
3.42 Rear Axle Ratio engineered for balanced towing strength and highway performance Â
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Winter & Weather Comfort Â
Heated & Ventilated Front Seats delivering year-round comfort Â
Heated Rear Outboard Seats for added second-row passenger luxury Â
Heated Steering Wheel for cold-weather driving comfort Â
Remote Vehicle Start System to warm or cool the cabin before departure Â
Dual-Zone Automatic Climate Control for personalized cabin temperatures Â
Engine Block Heater for dependable cold-weather starts Â
Rain-Sensing Windshield Wipers for improved visibility during changing weather conditions Â
Winter Grille Cover helping maintain engine temperature in extreme cold climates Â
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Interior Comfort & Technology Â
Front Bucket Seats with power driver and passenger adjustments Â
Premium Jet Black/Kalahari interior with AT4-exclusive styling details Â
Power Sliding Rear Window for added ventilation and convenience Â
Rear Seat Storage Package providing practical interior organization Â
Wireless Charging Pad and multiple USB ports for connected convenience Â
Push-Button Start and Keyless Open for effortless access and ignition Â
13.4" GMC Premium Infotainment Touchscreen with Google Built-In compatibility and navigation capability Â
12" Digital Driver Information Centre with customizable vehicle data displaysÂ
Bose® Premium Audio System delivering rich, immersive sound quality Â
Head-Up Display projecting key driving information directly onto the windshield Â
Rear Camera Mirror for a wider, less obstructed rearward view Â
Wi-Fi Hotspot Capability helping passengers stay connected on the road Â
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Safety & Driver Assistance Â
Sierra HD Pro Safety suite for enhanced confidence behind the wheel Â
Forward Collision Alert with Automatic Emergency Braking Â
Front Pedestrian Braking for improved urban safety awareness Â
Lane Departure Warning and Following Distance Indicator Â
Adaptive Cruise Control for smoother highway travel Â
HD Surround Vision providing a full 360-degree exterior view Â
Front & Rear Park Assist simplifying tight maneuvering Â
Trailer Side Blind Zone Alert for added towing awareness Â
Rear Cross Traffic Alert improving confidence while reversing Â
Teen Driver Technology and Buckle-to-Drive safety systems Â
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Exterior Styling & Utility Â
Exterior Colour: Summit White — clean, bold, and unmistakably professionalÂ
20" Black Aluminum Wheels wrapped in aggressive all-terrain tires Â
LED Headlamps, LED Fog Lamps, and LED Cargo Bed Lighting for outstanding visibility Â
Power Sunroof adding an open-air driving experience Â
GMC MultiPro Tailgate offering versatile loading and worksite functionality Â
Spray-On Bedliner and Rear Wheelhouse Liners for added durability and cargo protection Â
Power-Retractable Black Assist Steps with LED lighting for easier entry and exit Â
Red Front Recovery Hooks emphasizing the AT4’s rugged off-road character Â
Deep-Tinted Glass and bold AT4 exterior accents for a commanding appearance Â
Heated Power Trailering Mirrors with auto-dimming functionality for towing convenience Â
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Whether you’re hauling heavy equipment, towing a large trailer, or heading deep into the backcountry, the 2026 GMC Sierra 3500HD AT4 delivers uncompromising diesel capability, advanced technology, and premium comfort. It’s a heavy-duty truck engineered for drivers who demand strength, confidence, and refinement without compromise.Â
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Packages & Options
Standard Equipment
Technical Specifications
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AM/FM Stereo
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Auxiliary Audio Input
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Bluetooth Connection
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MP3 Player
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Navigation System
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Smart Device Integration
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Requires Subscription
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Satellite Radio
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Premium Sound System
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WiFi Hotspot
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Aluminum Wheels
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Tires - Front All-Terrain
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Tires - Rear All-Terrain
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Conventional Spare Tire
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Tire carrier lock keyed cylinder lock that utilizes same key as ignition and door
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Bumper, front, body-colour lower
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Bumper, rear body-colour with bumper CornerSteps
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CornerStep, rear bumper
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Bed Step, Black integrated on forward portion of bed on driver and passenger side
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Mouldings, beltline, Black
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Wheelhouse liners, rear
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Bed Liner
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Cargo tie downs (12), fixed, rated at 500 lbs per corner
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Grille, Gloss Black header and grille insert bars with Black chrome accents
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Daytime Running Lights
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LED Headlights
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Automatic Highbeams
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Fog Lamps
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Taillamps, Animated LED Signature Tail, Stop, turn and Reverse lamps
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Lamps, cargo area, cab mounted integrated with centre high mount stop lamp, with switch in bank on left side of steering wheel
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LED Cargo Area Lighting located in cargo bed activated with switch on centre switch bank or key fob
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Heated Mirrors
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Integrated Turn Signal Mirrors
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Power Folding Mirrors
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Power Mirror(s)
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Mirror caps, high gloss Black
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Intermittent Wipers
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Rain Sensing Wipers
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Variable Speed Intermittent Wipers
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Privacy Glass
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Door handles, body-colour
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Integrated Tailgate Step
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Tailgate and bed rail protection caps, top
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Tailgate, gate function manual with EZ Lift includes power lock and release, includes hitch area light
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Bucket Seats
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Leather Seats
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Driver Adjustable Lumbar
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Power Driver Seat
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Passenger Adjustable Lumbar
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Power Passenger Seat
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Pass-Through Rear Seat
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Rear Bench Seat
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Heated Front Seat(s)
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Cooled Front Seat(s)
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Heated Rear Seat(s)
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Mirror Memory
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Seat Memory
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Centre Console, floor-mounted with cup holders, cell phone storage, power cord management, hanging file folder capability
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Floor covering, colour-keyed carpeting
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Floor Mats
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Heated Steering Wheel
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Adjustable Steering Wheel
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Steering Wheel Audio Controls
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Driver Information Centre, enhanced, 12.3" diagonal reconfigurable multicolour digital display
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GMC Premium information Display- 13.4" diagonal Multicolour touch screen
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Exterior Temperature Display located in radio display
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Compass, located in instrument cluster
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Tire Pressure Monitor
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Window, power front, drivers express up/down
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Power Windows
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Power Door Locks
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Remote Engine Start
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Keyless Entry
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Keyless Start
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Adaptive Cruise Control
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Cruise Control
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Security System
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Wireless Charging
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Power outlet, instrument panel, 120-volt (400 watts shared with (KC9) bed mounted power outlet)
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USB ports, (2) charge-only, rear
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Auxiliary Audio Input
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MP3 Player
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Power outlet, bed mounted, 120-volt (400 watts shared with (KI4) instrument panel mounted power outlet)
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A/C
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Climate Control
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Multi-Zone A/C
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Air vents, rear
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Rear Defrost
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Auto-Dimming Rearview Mirror
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Assist handles, front A-pillar mounted for driver and passenger, rear B-pillar mounted
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8 Cylinder Engine
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Gasoline Fuel
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10-Speed A/T
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A/T
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Rear axle, 3.73 ratio (Requires (L8T) 6.6L V8 gas engine.)
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Running Boards/Side Steps
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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.)
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Keyless Start
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Air filter, heavy-duty
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Air filtration monitoring
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Transfer case, two-speed active electronic Autotrac with push button control
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Locking/Limited Slip Differential
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Four Wheel Drive
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Cooling, external engine oil cooler
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Cooling, auxiliary external transmission oil cooler
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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.)
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Alternator, 170 amps (Requires (L8T) 6.6L V8 gas engine.)
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Trailer brake controller, integrated
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Tow Hooks
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Frame, fully-boxed, hydroformed front section and a fully-boxed stamped rear section
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Skid Plates protect the oil pan, front axle and transfer case
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Suspension, Off-Road includes twin-tube shocks
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Power Steering
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4-Wheel Disc Brakes
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ABS
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Brake lining wear indicator
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Capless Fuel Fill (Requires (L8T) 6.6L gas V8 engine.)
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Automatic Highbeams
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Front Collision Mitigation
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Front Collision Warning
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Lane Departure Warning
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X31 Off-Road Package includes (JHD) Hill Descent Control, (NZZ) skid plates, Off-Road suspension and Twin-tube Rancho shocks
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Tow Hitch
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ProGrade Trailering System includes (PZ8) Hitch Guidance with Hitch View and (UET) In-vehicle Trailering App
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Trailering Information Label provides max trailer ratings for tongue weight, conventional, gooseneck and 5th wheel trailering
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Front Collision Mitigation
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Front Collision Warning
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Stability Control
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Traction Control
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Hill Descent Control
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Daytime Running Lights
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Driver Air Bag
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Front Head Air Bag
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Front Side Air Bag
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Passenger Air Bag
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Passenger Air Bag Sensor
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Rear Head Air Bag
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Requires Subscription
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Telematics
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Rear Parking Aid
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Aerial View Display System
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Back-Up Camera
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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
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Hitch Guidance dynamic single line to aid in truck trailer alignment for hitching
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Trailer Camera Provisions and trailer viewing software
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Cross-Traffic Alert
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Blind Spot Monitor
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Lane Departure Warning
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Following Distance Indicator (Included and only available with (PDI) Sierra HD Pro Safety.)
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Safety Alert Seat
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Rear Seat Reminder
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Driver Restriction Features
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Seat Belt Adjustable Guide Loops, front row only
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Rear Seat Belt Indicator (Requires Crew Cab or Double Cab model.)
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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)
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Tire Pressure Monitor
No matches were found.
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Vehicle NameGMC Sierra 3500HD
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Body StyleCrew Cab Pickup
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Body CodeE63
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DrivetrainFour Wheel Drive
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Trans Order CodeMGM
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Trans Type10
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Trans Description Cont.Automatic
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First Gear Ratio (:1)4.54
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Second Gear Ratio (:1)2.87
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Third Gear Ratio (:1)2.06
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Fourth Gear Ratio (:1)1.72
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Fifth Gear Ratio (:1)1.48
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Sixth Gear Ratio (:1)1.26
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Seventh Gear Ratio (:1)1.00
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Eighth Gear Ratio (:1)0.85
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Ninth Gear Ratio (:1)0.69
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Tenth Gear Ratio (:1)0.63
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Reverse Ratio (:1)4.54
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Passenger Capacity5
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Front Head Room (in)39.88
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Front Leg Room (in)44.53
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Front Shoulder Room (in)66.02
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Front Hip Room (in)61.18
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Second Head Room (in)40.12
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Second Leg Room (in)43.4
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Second Shoulder Room (in)65.3
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Second Hip Room (in)60.24
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Gross Axle Wt Rating - Front (lbs)5600
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Gross Axle Wt Rating - Rear (lbs)7250
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Curb Weight - Front (lbs)4032
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Curb Weight - Rear (lbs)2928
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Gross Vehicle Weight Rating Cap (lbs)12100
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Gross Combined Wt Rating (lbs)30000
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Dead Weight Hitch - Max Trailer Wt. (lbs)5000
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Dead Weight Hitch - Max Tongue Wt. (lbs)500
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Wt Distributing Hitch - Max Trailer Wt. (lbs)20000
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Wt Distributing Hitch - Max Tongue Wt. (lbs)2000
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Fifth Wheel Hitch - Max Trailer Wt. (lbs)21300
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Fifth Wheel Hitch - Max Tongue Wt. (lbs)5325
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Maximum Trailering Capacity (lbs)20000
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Engine Order CodeL5P
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Engine TypeTurbocharged Diesel V8
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Displacement6.6L
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Fuel SystemDirect Injection
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SAE Net Horsepower @ RPM470 @ 2800
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SAE Net Torque @ RPM975 @ 1600
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Engine Oil CoolerYes
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Cold Cranking Amps @ 0° F (Primary)720
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Maximum Alternator Capacity (amps)220
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Frame TypeHydroformed
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Suspension Type - FrontShort/Long Arm w/Torsion Bars
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Suspension Type - Rear3-Stage Multi-Leaf
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Axle Type - FrontIndependent
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Axle Ratio (:1) - Front3.42
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Axle Ratio (:1) - Rear3.42
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Shock Absorber Diameter - Front (mm)51
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Shock Absorber Diameter - Rear (mm)51
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Stabilizer Bar Diameter - Front (in)1.38
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Front Tire Order CodeQF9
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Rear Tire Order CodeQF9
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Spare Tire Order CodeZYG
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Front Tire SizeLT275/65R20
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Rear Tire SizeLT275/65R20
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Spare Tire SizeLT275/70R18
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Front Wheel Size (in)18 x 8
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Rear Wheel Size (in)18 x 8
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Spare Wheel Size (in)18 x 8
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Front Wheel MaterialAluminum
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Rear Wheel MaterialAluminum
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Spare Wheel MaterialSteel
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Steering TypePwr Recirculating Ball
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Steering Ratio (:1), At LockN/A
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Turning Diameter - Curb to Curb (ft)52.7
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Turning Diameter - Wall to Wall (ft)N/A
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Brake TypePwr
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Brake ABS System4-Wheel
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Disc - FrontYes
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Disc - RearYes
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Front Brake Rotor Diam x Thickness (in)14 x 1.6
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Rear Brake Rotor Diam x Thickness (in)14.1 x 1.3
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Fuel Tank Capacity, Approx (L)136
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Wheelbase (in)158.94
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Length, Overall (in)250.75
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Width, Max w/o mirrors (in)81.85
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Height, Overall (in)81.2
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Cab to Axle (in)42.17
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Ground Clearance, Front (in)11.18
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Ground Clearance, Rear (in)11.18
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Cargo Box Length @ Floor (in)82.2
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Cargo Box Width @ Floor (in)71.4
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Cargo Box Width @ Wheelhousings (in)51.85
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Cargo Box (Area) Height (in)21
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Cargo Volume (ft³)69.5
No matches were found.
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