2026 GMC Sierra 2500 HD AT4

  • New
  • Diesel
$91,125$91,625 MSRP
Value Your Trade
CASPER GMC CADILLAC
Location Details
Call 307-224-2982
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    The overview

    Exterior Color
    Titanium Rush Metallic
    Interior Color
    Jet Black with Kalahari accents, Perforated Front
    Transmission
    Automatic
    Drivetrain
    4WD
    Engine
    6.6L Duramax Turbo-Diesel V8 engine
    VIN
    1GT4UPEY3TF191802
    Stock Number
    G7279
      • Basic: 3 Years/36,000 Miles
      • Corrosion: 3 Years/36,000 Miles, Rust-Through, 6 Years/100,000 Miles
      • Drivetrain: 5 Years/60,000 Miles, 3.0L & 6.0L Duramax® Turbo-Diesel engines, and certain commercial, government, and qualified fleet vehicles: 5 years/100,000 miles
      • Maintenance: First Visit: 12 Months/12,000 Miles
      • Roadside Assistance: 5 Years/60,000 Miles, 3.0L & 6.0L Duramax® Turbo-Diesel engines, and certain commercial, government, and qualified fleet vehicles: 5 years/100,000 miles
      • Warranty: <<< Preliminary 2026 Warranty >>>
      • Max seating capacity: 5
      • Fuel System: Direct Injection
      • Fuel tank capacity: 36 gal
      • Horsepower: 470
      • Towing capacity: 18500 lbs
      • 13.4" diagonal GMC Premium Infotainment System with Google built-in:
        • 13.4" diagonal GMC Premium Infotainment System with Google built-in, includes multi-touch display, AM/FM/SiriusXM1 radio capable
        • Bluetooth®2 streaming audio for music and select phones
        • Wireless Apple CarPlay™ capability for compatible phones3
        • Wireless Android Auto™ capability for compatible phones4
        • Customize and manage entertainment and vehicle feature setting
        • Use, control and manage select smartphone apps through the Infotainment system
        • Voice-activated technology for phone
      • Bluetooth®:
        • Pair your compatible mobile phone to your vehicle's infotainment system1
        • Place and receive hands-free phone calls
        • Store your phone's contact list in the system to place an outgoing call quickly using the touch-screen display or voice command system
        • With streaming audio capability, you can listen to files stored on your phone or Bluetooth digital media device
      • Bose Premium Sound System:
        • 7-speakers with Richbass® woofer
        • Bose is renowned for expert sound engineering and high-quality audio and with premium speakers positioned throughout the cabin
        • May require additional optional equipment
      • SiriusXM with 360L Trial Subscription:
        • With your trial subscription, new GM vehicles equipped with SiriusXM with 360L advance in-car technology will bring you closer to your favorite stars, artists, creators, hosts and athletes1
        • SiriusXM with 360L transforms your ride with our most extensive and personalized radio experience on the road that lets you enjoy ad-free music, talk and news, live sports, comedy, podcasts and more
        • Experience SiriusXM wherever you go in your vehicle and on the SiriusXM app with personalization features to make discovering your perfect entertainment easier than ever before
      • Wi-Fi® Hotspot capable:
        • Terms and limitations apply. See onstar.com or dealer for details.
        • May require additional optional equipment
      • Wireless phone projection:
        • For Apple CarPlay™1 and Android Auto™2
      • 18" LT275/70R18 all-terrain, blackwall spare tire:
        • May require additional optional equipment
      • 20" LT275/65R20 BF Goodrich off-road T/A K blackwall tires
      • 20" high gloss Black aluminum wheels
      • Animated LED Signature Tail lamps with Stop, turn and Reverse lamps:
        • LED taillamps with LED stop lights and animation
      • Animated LED projectors headlamps with LED turn signals and Daytime Running Lamps
      • Black beltline moldings
      • Black power-retractable assist steps with LED perimeter lighting:
        • Textured step pads help provide secure footing
        • Retracts when not in use
        • Deploy Running Board mode for car wash cleaning
        • LED perimeter lighting
        • May require additional optional equipment
      • Body color wheel arch moldings:
        • Available in (Summit White, White Frost Tricoat, Onyx Black, Volcanic Red Tintcoat or Sterling Metallic)
      • Body-color door handles
      • Body-color front bumper
      • Body-color rear bumper:
        • With integrated CornerSteps
      • Cab-mounted cargo area lamps:
        • Activated by switch located on center switch bank
        • Illuminates the cargo bed area
      • Cargo bed LED lighting:
        • Provides light to find cargo in the bed
        • May require additional optional equipment
      • Cargo tie-downs:
        • 12-fixed rated at 500 lbs. per corner
      • CornerStep rear bumper:
        • Helps make it easier to get into and out of the pickup bed
        • Located at each end of the rear bumper
        • Textured step pads to help provide secure footing
      • Deep-tinted glass:
        • Provides added protection from sun and glare
      • Front license plate bracket:
        • Front bracket is included if displaying a front license plate is required in your state
      • GMC MultiPro Tailgate:
        • Six function tailgate designed to help improve loading, unloading and accessing the cargo box
        • Hitch area lighting
        • Power lock and release
        • May require additional optional equipment
      • High gloss Black mirror caps
      • IntelliBeam:
        • At speeds above 25 mph, can automatically turn vehicle's high beams on and off according to surrounding traffic conditions1
      • LED fog lamps
      • Outside power-adjustable vertical trailering mirrors with power folding/extending auto-dimming driver and passenger upper glass:
        • Chrome mirror caps
        • AT4 and AT4X features high gloss Black mirror caps
        • Power folding/extending
        • Lower convex mirrors
        • Heated upper glass
        • Integrated turn signal indicators
        • Puddle lamps
        • Perimeter lighting
        • Auxiliary lighting
        • Extends 3.31-inches
      • Power sunroof:
        • Opens over the first row at the push of a button
        • Retracts into the roof
        • Offers tilt and slide features with express-open and -close
        • May require additional optional equipment
      • Rainsense automatic wipers:
        • When turned on, will automatically clear the windshield when sensors detect varying degrees of precipitation on the windshield
      • Rear wheelhouse liners:
        • Help protect your truck's rear wheelhouse area from damage caused by dirt, rocks, mud, road salt and the weather
        • May require additional optional equipment
      • Side Bed Step:
        • Black textured step pads help provide secure footing
        • Integrated on forward portion of outer bed on driver and passenger side to provide ease of access to forward portion of the bed
      • Smoked Amber LED roof marker lamps:
        • Roof-mounted lamps near the front of the cab
      • Spare tire carrier lock:
        • Helps keep spare tire secure
      • Spray-on bedliner:
        • Provides a Black, textured, non-skid surface that helps protect the bed and minimizes cargo shifting
        • Covers the entire bed surface below side rails, front box top rail, gauge hole plugs and tie-downs
        • Chemically bonded, the sprayed-on liner permanently bonds to the truck bed, providing a watertight seal
        • Does not include spray-on liner on tailgate due to Black composite inner panel
        • Includes GMC logo on all trims except PRO
      • Tailgate and bed rail protection caps
      • Tailgate with EZ Lift assist, power lock & release:
        • Hitch area lighting
        • May require additional optional equipment
      • Winter Grille Cover:
        • May require additional optional equipment
      • 10-way power driver seat with power lumbar:
        • Includes 8-way power driver seat
        • Includes a 2-way power lumbar control
      • 10-way power front passenger seat:
        • Includes 8-way power front passenger seat
        • Includes a 2-way power lumbar control
      • 12.3" diagonal color Driver Information Center:
        • Includes driver personalization, warning messages and vehicle information
        • Replaces traditional analog gauges with fully reconfigurable high definition cluster layout
        • High definition display provides crisp, premium appearance
      • 120-volt box-mounted power outlet:
        • 3-prong auxiliary household-style outlet
        • Located in the pickup bed
        • May require additional optional equipment
      • 120-volt power outlet:
        • 3-prong auxiliary household-style outlet
        • Located on the instrument panel
        • Makes it convenient for powering laptops, phone chargers and other electronic devices
        • May require additional optional equipment
      • 13.4" diagonal GMC Premium Infotainment System with Google built-in:
        • 13.4" diagonal GMC Premium Infotainment System with Google built-in, includes multi-touch display, AM/FM/SiriusXM1 radio capable
        • Bluetooth®2 streaming audio for music and select phones
        • Wireless Apple CarPlay™ capability for compatible phones3
        • Wireless Android Auto™ capability for compatible phones4
        • Customize and manage entertainment and vehicle feature setting
        • Use, control and manage select smartphone apps through the Infotainment system
        • Voice-activated technology for phone
      • Adaptive Cruise Control:
        • Automatically follows a detected vehicle ahead at a driver-selected following gap1
        • If no vehicle is detected in your path, works like regular cruise control
        • You can always override the feature and take control
        • Adaptive Cruise Control is compatible with Trailering. It is important to ensure your trailer has functioning brakes while trailering with heavier loads. Read your Owner's Manual to review Trailer Brake requirements and to learn more about the limitations of this system.
      • Assist handles:
        • Front A-pillar mounted for Driver and Passenger
        • Rear B-pillar mounted
      • Carpeted floor covering:
        • Color-keyed to match the interior
      • Compass:
        • Located in instrument cluster
      • Driver memory:
        • Press memory button 1 or 2 to program and recall preferences
        • May require additional optional equipment
      • Dual-zone automatic climate control:
        • Automatically maintains the selected temperatures for both the driver and front passenger
        • Allows individual climate settings for both driver and front passenger
        • Driver and front passenger can choose a temperature up to 30 degrees difference
        • May require additional optional equipment
      • Front bucket seats:
        • May require additional optional equipment
      • Front center console:
        • Includes reconfigurable feature with cupholders, cell phone storage, power cord management and file holder capacity
        • May require additional optional equipment
      • Head-Up Display:
        • Projects vehicle information onto the windshield low in the driver's line of sight to help you keep your eyes on the road1
        • Multi-color 15" diagonal Head-Up Display
        • Can select key vehicle information to display including an off-road inclinometer
        • Adjustable vertical position and brightness of the display
        • May require additional optional equipment
      • Heated driver and front outboard passenger seats:
        • Separate buttons on the climate control panel allow you to choose from 3 levels of warmth
        • At the touch of a button you can warm the cushions and seatbacks with multilevel temperature control
        • Individually controlled
        • Seats can be programmed to automatically warm up when it's cold out
        • May require additional optional equipment
      • Heated rear outboard seats:
        • At the touch of a button you can warm the cushions
        • Provide comfort in cold weather for passengers in the rear outboard seating positions
        • Passengers can manage heat settings with their own controls
        • May require additional optional equipment
      • Heated steering wheel:
        • With the press of a button the steering wheel quickly heats up to provide additional comfort on a cold day
        • May require additional optional equipment
      • Inside rearview auto-dimming mirror:
        • Automatically dims the inside rearview mirror when it senses bright light from behind
        • When headlamp glare is no longer detected, the mirror returns to its normal state
      • Keyless Open and Start:
        • With the key fob in your possession, lock and unlock your car's doors by pressing the button on a front exterior door handle, increasing convenience
        • Lockout protection helps you avoid locking keys in the vehicle
      • Manual tilt and telescoping steering column:
        • Allows the driver to adjust the steering wheel up or down, and the steering column forward or back
        • May require additional optional equipment
      • Outside temperature display:
        • Located in infotainment display
      • Power door locks:
        • Allows you to lock and unlock doors easily whether it's from the driver or front passenger seat or from outside using the key fob (when equipped)
      • Power sliding rear window with rear defogger:
        • Utilizes a warming grid to remove fog or frost from the rear window
        • The window switch is conveniently located in the overhead console for easy 1-touch operation
        • May require additional optional equipment
      • Power windows with driver and front passenger express-up/down:
        • Quickly raises the window or lowers it with the touch of a button
        • If obstruction is detected, the anti-pinch feature will auto-reverse
      • Power windows with driver express-up/down:
        • Quickly raises the window or lowers it with the touch of a button
        • If an obstruction is detected, the anti-pinch feature will auto-reverse
      • Power windows with rear express-down
      • Premium front floor liners with removable carpet insert
      • Premium rear floor liners with removable carpet insert
      • Rear Camera Mirror:
        • Uses a camera to provide you with the option of using a wide and less obstructed view behind your vehicle while driving instead of a traditional rearview mirror1
        • The feature also allows brightness, vertical tilt and zoom adjustments
        • May require additional optional equipment
      • Rear Seat Reminder:
        • Helps to remind the driver to check the back seat(s) before leaving the vehicle1
        • Activates when rear doors are opened and closed up to 10 minutes before or anytime while your vehicle is on
        • Under certain conditions, once the vehicle is switched off, designed to sound audible chimes and display a visual message within the driver display
        • Activates only once each time the vehicle is turned on and off, and would require re-activation on a second trip
      • Rear air vents:
        • Provides cabin comfort for rear occupants
      • Rear window defogger:
        • Utilizes a warming grid to help remove fog or frost from the rear window
      • Remote Start:
        • Start your vehicle remotely and step into a comfortably warmed or cooled vehicle, depending on the weather and your preset preferences
        • Locks doors and turns on parking lamps while the engine is running
        • Activates the climate control system
      • Steering-wheel mounted controls:
        • Allow the driver to easily operate the audio system and phone interface controls
        • May require additional optional equipment
      • Theft-deterrent unauthorized entry system:
        • Sounds the horn and flashes the turn signals when someone attempts to open the vehicle without the proper key or remote transmitter
        • Helps deter unauthorized entry, helping to protect your vehicle
        • May require additional optional equipment
      • USB ports:
        • (2) Charge ports located on rear of console1
      • USB ports:
        • (2) Data/charge ports located inside center console1
      • USB ports:
        • (2) First row, located on console1
      • Universal Home Remote:
        • 3-channel programmable
        • Conveniently activates compatible devices such as garage door openers, security systems, and home automation devices from inside your vehicle
        • May require additional optional equipment
      • Up-level rear seat with storage package:
        • 60/40 Full-length folding bench seat
        • Seatback storage on left and right side
        • Center fold out armrest with 2 cupholders
        • Underseat storage (full cab width)
      • Ventilated driver and front passenger seats:
        • Separate buttons on the climate control panel allow you to choose from 3 levels of fan circulation
        • Individually controlled
        • Cooling feature includes both seatbacks and cushions
        • May require additional optional equipment
      • Wireless Charging:
        • Uses induction technology for select portable electronic devices1
        • Convenient charging location
        • Customers can charge their smartphones while they drive without connecting to any cables
        • May require additional optional equipment
      • Wrapped steering wheel
      • 10-speed automatic transmission:
        • Tow/Haul mode reduces shift cycling for better control and improved cooling when towing or hauling heavy loads
        • Electronically controlled with overdrive
        • Auto Grade Braking that automatically downshifts when needed to enable engine braking, helping to slow the vehicle on downhill grades and reduce brake wear (operates in Tow/Haul mode)
        • May require additional optional equipment
      • 11,350 lbs. GVWR:
        • When properly equipped; includes weight of vehicle, passengers, cargo and equipment
      • 220-amp alternator:
        • May require additional optional equipment
      • 3.42 rear axle ratio:
        • Requires a diesel engine
      • 4-wheel antilock disc brakes:
        • Help reduce wheel lockup and maintain steering control during hard braking on most slippery surfaces
        • DuraLife™ brake rotors feature a hardened surface to reduce corrosion and provide quieter braking with less vibration. DuraLife™ rotors are hardened and strengthened during the manufacturing process
        • Brake system features a corrosion-fighting process called Ferritic Nitro-Carburizing (FNC) which can double rotor life expectancy and reduce or minimize rust over non-FNC coated rotors
      • 6.6L Duramax Turbo-Diesel V8 engine:
        • 470 hp [350.5 kW] @ 2800 rpm
        • 975 lb-ft of torque [1322 Nm] @ 1600 rpm
        • 3.42 rear axle ratio
        • Exhaust brake
        • Engine block heater
        • Capped fuel fill
        • Paired with an Allison® 10-speed automatic transmission
        • Diesel Exhaust Fluid (DEF) fill located in fuel door
        • Engine after run feature for cooling performance
        • May require additional optional equipment
      • Air filtration monitoring:
        • Alerts the driver when the engine air filter needs replacement
      • Automatic locking rear differential:
        • When the differential senses a significant difference in wheel speed, it locks to turn both rear wheels in unison for added traction
        • The Eaton® Locker senses a difference in wheel speed of approximately 100 rpm
      • Autotrac® 2-speed transfer case with push button controls:
        • 4-button control 2WD, Auto, 4WD, 4WD LO
        • 2WD High for most on-road and highway situations
        • 4WD High for snowy or wet roads when added traction is needed
        • 4WD Low for deep sand, mud or snow to provide maximum torque to all 4 wheels
        • When in AUTO mode, remains in 2WD mode until the system detects wheel slippage
          • Automatically engages 4WD until traction is regained
        • May require additional optional equipment
      • Brake pad wear indicator
      • Capped fuel fill:
        • Requires diesel engine or pickup bed delete
      • Diesel exhaust brake:
        • Reduces the amount of conventional braking needed while towing a heavy trailer or driving downhill
        • Uses the variable vanes in the turbocharger to smoothly and quietly create additional back pressure in the engine to help slow the vehicle
        • Works with the transmission's Tow/Haul mode and Auto Grade Braking to help the driver maintain the desired speed even on long, steep downgrades
        • Switch activated
        • May require additional optional equipment
      • Digital Variable Steering Assist:
        • This system automatically adjusts steering based on speed, road conditions, and other inputs to help reduce driver fatigue
      • Engine block heater:
        • Helps ease cold weather starts
        • Heats the engine and engine block fluids
      • External auxiliary transmission oil cooler:
        • Heavy-duty air-to-oil cooler
        • Helps provides optimal transmission performance even when operating under a heavy load or towing a trailer
        • May require additional optional equipment
      • External engine oil cooler:
        • Heavy-duty air-to-oil cooler
        • Helps extend engine oil life under heavy loads
      • Fully boxed frame:
        • Hydroformed front section
        • High-strength steel
      • Gooseneck / 5th Wheel Prep Package:
        • Hitch platform to accept Gooseneck or 5th wheel hitch
        • Hitch platform with tray to accept ball and stamped box holes with caps installed
        • Box mounted 7-pin trailer harness
        • May require additional optional equipment
      • Heavy-Duty Air Filter:
        • Thick construction helps to trap more dirt before it can enter the air intake
      • Heavy-duty dual batteries with 1460 cold-cranking amps:
        • 70 Amp-hr
        • Maintenance-free with rundown protection and retained accessory power
        • May require additional optional equipment
      • High idle switch:
        • Runs the engine in High Idle mode, holding the engine at approximately 1200 rpm
        • Operates using the cruise control buttons on the steering wheel
        • High Idle mode is deactivated when you turn off the truck or before you drive off
        • May require additional optional equipment
      • Hill Descent Control:
        • Uses antilock braking to help provide a smooth, controlled descent
        • Helps driver maintain control of the vehicle without depressing the brake pedal
        • Activates by pushing a button below the instrument panel
        • May require additional optional equipment
      • In-Vehicle Trailering App:
        • Checklist1
        • Trailer maintenance reminders
        • Trailer security alerts
        • Trailer mileage
        • Tow/haul reminder
        • Trailer electrical diagnostics
        • Includes trailer tire pressure monitoring alert ONLY when (PTT) trailer tire pressure monitor system is factory ordered and sensors are installed
      • Integrated trailer brake controller:
        • Integrated with the antilock brake system (ABS)
        • Helps provide measured brake force signaling to electric-controlled trailer brake systems
        • Trailer gain and output are displayed in the Driver Information Center
      • Off-Road suspension:
        • May require additional optional equipment
      • Pickup bed:
        • Roll-formed high-strength steel
        • Includes bed assist step
      • Push Button Start
      • Red vertical recovery hooks:
        • Two front frame-mounted1
      • Skid plates:
        • Help protect the front underbody, oil pan and transfer case
        • May require additional optional equipment
      • AT4 Preferred Package:
        • Universal Home Remote
        • Rear sliding power window
        • LED roof marker lamps
      • AT4 Premium Plus Package:
        • AT4 Preferred Package
        • Power sunroof
        • Technology Package
        • AT4 high clearance step
        • May require additional optional equipment
      • Gooseneck Hitch Package:
        • Gooseneck ball
        • Chain tiedown kit with case
        • May require additional optional equipment
      • ProGrade Trailering System:
        • Hitch Guidance with Hitch View
        • In-vehicle Trailering App
      • Sierra HD Pro Safety:
        • Forward Collision Alert1
        • Following Distance Indicator1
        • Front Pedestrian Braking1
        • IntelliBeam
        • Lane Departure Warning1
        • Buckle to Drive
        • Automatic Emergency Braking1
      • Technology Package:
        • Rear Camera Mirror1
        • Multi-color 15" Diagonal Head-Up Display
        • AT4 Preferred Package on AT4
        • May require additional optional equipment
      • Trailering Package:
        • Trailer hitch1
        • Trailering hitch platform
        • Includes a 2.5" receiver hitch (with 2" insert), 4-pin and 7-pin connectors
        • 7-wire electrical harness and 7-pin sealed connector for connecting your trailer's lights and brakes to your vehicle
        • Hitch Guidance2
        • May require additional optional equipment
      • X31 Off-Road Package:
        • Off-Road suspension
        • Hill Descent Control
        • Skid plates
        • Twin-tube Rancho shocks
      • LED Daytime Running Lamps
      • Signature LED Daytime Running Lamps
      • 6 airbags:
        • Dual-stage frontal airbags for driver and front outboard passenger1
        • Seat-mounted side-impact airbags for driver and front outboard passenger1
        • Head-curtain airbags for outboard seating positions1
        • Includes front outboard Passenger Sensing System for frontal outboard passenger airbag and illuminates a status light that indicates whether the airbag is on or off1
      • Bed View Camera:
        • Camera in the Center High Mount Stop Lamp (CHMSL) provides an elevated view of the truck bed from the back of the cab1
        • Allows driver to see inside the cargo bed on the infotainment display to help with 5th wheel or gooseneck hitching and to check cargo
        • Includes 2 Trailer Camera Provisions
        • May require additional optional equipment
      • Buckle to Drive:
        • Helps remind the driver to buckle their seat belt before driving by preventing the vehicle from being shifted out of PARK temporarily when the driver's seat belt is not buckled
        • The feature also reminds the front passenger to buckle up, if equipped
      • Following Distance Indicator:
        • Displays the following time in seconds between your vehicle and a detected vehicle in front of you1
        • Designed to help you maintain a safe following distance
      • Forward Collision Alert:
        • Warns you if it detects a potential collision with a detected vehicle you're following so you can take action1
        • Can also provide a tailgating alert if you're following a vehicle much too closely
      • Front and Rear Park Assist:
        • Provides alerts of nearby detected vehicles and objects in front of or behind your vehicle1
        • These can help you park and avoid collisions
        • May require additional optional equipment
      • HD Surround Vision:
        • Provides selectable digital camera views of the area around your vehicle1
        • Can help you park or avoid vehicles and objects1
        • You can also display a guideline to show where your vehicle is heading1
        • Tailgate must be in the raised position for the HD Rear Vision Camera to operate properly
        • Requires Auxiliary Trailer Camera if one of the following camera views is desired: Transparent Trailer, Rear Trailer View, Picture-in-Picture or Inside Trailer View
        • May require additional optional equipment
      • Hitch Guidance:
        • When in Reverse, displays a centered guideline on the Rear Vision Camera view1
        • Can help you line up the hitch to your trailer
        • When driving, lets you check the trailer using Rear Vision Camera view
      • Hitch View:
        • Shows a close-up view of the trailer hitch1
        • In Reverse, the view can be used to line up your hitch to your trailer
        • When driving, the view can be used to check your trailer hitch
        • Shifting to Park automatically engages the Electric Parking Brake (if equipped)
        • May require additional optional equipment
      • Lane Departure Warning:
        • Alerts you when it detects that you are unintentionally drifting out of detected lane lines1
        • System alerts do not occur if you're using your turn signal, or it detects you may be intentionally leaving your lane
      • OnStar Basics:
        • Drive confidently with core OnStar services including1
          • Remote commands
          • Built-in voice assistance
          • Real-time traffic and navigation
          • Automatic Crash Response
      • OnStar® services capable:
        • See onstar.com for details and limitations. Services vary by model. Service plan required.
      • Rear Cross Traffic Alert:
        • When in Reverse, warns you of detected vehicles crossing behind you1
        • May require additional optional equipment
      • Rear Seat Belt Indicator
      • Safety Alert Seat:
        • Uses left-, right- or both-side driver seat vibration pulses to help you detect and identify the direction of potential crashes1
        • You can also switch to beeping crash avoidance alerts
        • May require additional optional equipment
      • Seat Belt Adjustable Guide Loops:
        • Front row only
      • Teen Driver:
        • Helps encourage safe driving habits for teens by providing an in-vehicle report card1
        • Activates certain safety systems, if equipped, when a Teen Driver-designated key fob is used
        • Mutes the radio until the front-seat occupants fasten their seat belts
      • Tire Pressure Monitoring System with Tire Fill Alert:
        • Monitors tire pressure and alerts of an under-inflated condition in one or more of the tires1
        • Provides visual and audible alerts outside the vehicle when inflating an under inflated tire to the recommended tire pressure
      • Trailer Side Blind Zone Alert:
        • Provides visual side-mirror alerts when a moving vehicle is detected in a side blind zone that is extended to trailer lengths1
        • May require additional optional equipment
      • Trailering Information Label:
        • Provides max trailer ratings for tongue weight, conventional, gooseneck hitch and 5th wheel hitch
      • Trailering camera provisions:
        • Includes connector for accessory wiring harness
      • Automatic Emergency Braking:
        • Can help you avoid or reduce the severity of a collision with a detected vehicle you're following using camera technology1
        • Can automatically provide hard emergency braking or enhance your hard braking
        • Works at speeds between 5 and 50 mph
      • Front Pedestrian Braking:
        • At speeds between 5 and 50 mph, can help you avoid or reduce the severity of a collision with a pedestrian it detects directly in front of you1
        • Provides pedestrian alerts and can automatically provide hard emergency braking or enhance driver's hard braking
        • Limited nighttime and low visibility performance
      • StabiliTrak, electronic stability control system with traction control:
        • Automatically helps enhance control, particularly during emergency maneuvers, by adjusting the brakes and engine torque to help you stay on your intended path
        • Activates when vehicle sensors detect a difference between the driver's intended path and the direction the vehicle is actually travelling
        • Includes Traction Control that detects wheel slippage and applies brake pressure and/or reduces engine power to help the driver maintain control when accelerating on wet or snow-covered roads
        • Includes Brake Assist which detects rapid brake pedal applications due to emergency braking situations and provides additional braking via the Antilock Brake System (ABS) module
        • Includes Trailer Sway Control
        • Hill Start Assist
      Vehicle Details
      Experience rugged capability and refined comfort with this 2026 GMC Sierra 2500 AT4 4WD, equipped with a powerful V8 6.6L diesel engine. Built for heavy-duty performance and towing confidence, this GMC Sierra pairs exceptional torque and durability with an upscale AT4 interior. Located in Casper, WY, this truck is offered at the best price priced competitively for buyers who demand value and capability. This GMC Sierra 2500 AT4 features premium leather seats and an Off Road Package that enhances ground clearance, skid protection, and suspension tuning for confident trail performance. Stay connected and entertained with Apple CarPlay integration and XM Radio, plus hands-free Bluetooth for safe, convenient calling and streaming on the go. The cabin blends utility and comfort with durable materials, modern technology, and driver-focused controls. Safety and convenience features are designed to handle worksite demands and weekend adventures alike. The 4WD system, heavy-duty diesel V8, and reinforced chassis make this GMC Sierra a top choice for towing, hauling, and off-road exploration across Wyoming terrain. Whether navigating city streets or climbing mountain passes, this truck delivers reliable performance and refinement. Visit our Casper, WY location to test drive this GMC Sierra 2500 AT4 and see why it represents the best value in heavy-duty pickups. Competitive financing and expert service support are available to make ownership seamless.

      Equipment
      Keep your hands warm all winter with a heated steering wheel in the GMC Sierra . Protect this vehicle from unwanted accidents with a cutting edge backup camera system. An off-road package is equipped on this unit. This GMC Sierra offers Android Auto for seamless smartphone integration. This model's Lane Departure Warning keeps you safe by alerting you when you drift from your lane. This vehicle features steering wheel audio controls. This vehicle has auto-adjust speed for safe following. Bluetooth technology is built into the vehicle, keeping your hands on the steering wheel and your focus on the road. The leather seats in this model are a must for buyers looking for comfort, durability, and style. Start the vehicle from inside with remote start. It warns of approaching vehicles with Cross-Traffic Alert. Engulf yourself with the crystal clear sound of a BOSE sound system in it. with XM/Sirus Satellite Radio you are no longer restricted by poor quality local radio stations while driving this 3/4 ton pickup. Anywhere on the planet, you will have hundreds of digital stations to choose from.

      Packages
      AT4 Premium Plus Package: Power Sunroof; Technology Package; Power-Retractable Black Assist Steps. Preferred Equipment Group 4SB: LED Cargo Area Lighting; Trailer Side Blind Zone Alert; SiriusXM with 360L Trial Subscription; Remote Vehicle Starter System; Safety Alert Seat; Ultrasonic Front and Rear Park Assist; Trailer Cam Provisions and Trailer Viewing Software; Electric Rear-Window Defogger; Floor-Mounted Center Console; Gloss Black Header Grille and Grille Insert Bars; Unauthorized Entry Theft-Deterrent System; Bed View Camera with Two Trailer Camera Provisions; Front Rain-Sensing Wipers; Sierra HD Pro Safety; Wireless Phone Projection; 2 USB Ports; Rear Cross Traffic Alert; 120-Volt Instrument Panel Power Outlet; 2 Charge/data USB Ports Inside Center Console; Heated Driver and Front Outboard Passenger Seats; Wireless Charging;

      Peace of mind

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      CASPER GMC CADILLAC is dedicated to your satisfaction before, during, and after your purchase. We'll go the extra mile to take care of you.
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      KBB.com Consumer Reviews

      Kelley Blue Book Logo3.8out of 5 overall
      • 2.0

        Transmission trash

        by Jason on Monday, April 07, 2025

        Bought a 2023 GMC Duramax diesel Sierra SLT had it for two years hit 50,000 miles. The throttlebody broke went in for service. Got it back three weeks at 62,000 miles now my transmission is slipping. I travel back-and-forth from South Carolina to North Carolina for work daughter’s truck would be my forever truck. What a joke Hundred thousand dollar truck junk…
      • 3.0

        Infotainment system unreliable!

        by Brian C on Friday, June 27, 2025

        The servicing dealer has been great, the GM engineers not so much! The truck will without warning have no sound for the radio and the blinkers. GM told the dealership to reprogram then when that didn't work they said replace the amplifier and when that didn't work, they said replace a module, and when that didn't work they said to replace the amplifier again, and when that didn't work they said we know it's a known problem but we don't know how to fix it. All of this with less than 9k miles. The dealer has done everything that GM has asked them to do, but none of it works. It's very frustrating to pay this much for a truck and you can't get the radio to stay working. It also got away from the factory with paint damage and a dent in the hood,( the dent is from the inside out on a double wall). I thought I was upgrading when I went from a F250 Lariat to a Denali, but I may have traded one headache for another.…
      • 5.0

        Fantastic truck

        by Jjj on Sunday, November 07, 2021

        This one of the most solid vehicles that I have ever driven! The 401 hp engine is more than enough power and the transmission is smooth! Highly recommend this truck!…
      Based on 13 consumer ratings for 2020–2026 models. Privacy