2020 GMC Sierra 2500HD AT4 with the 6.6L Duramax is a serious workhorse. Heres why it stands out:Off-road ready with off-road suspension, skid plates, Rancho shocks, and hill descent control
4WD standard with a locking rear differential
Aggressive styling with dark chrome accents and unique AT4 badging
Available Multicolor Head-Up Display and 360 camera system helps in tight job sites or towing
Used 2020 GMCSierra 2500HD AT4 Truck Duramax V8 Turbodiesel
We Do Business Your Way.™
- Our Absolute BEST Price, Up-Front, Every Time.
- NO Dealer Fees, Hidden Fees or Bogus Mark Ups.
- Non-Commissioned Salespeople.
- 3 Day/300 Mile Money Back Guarantee.
- Exterior Color
- Red Quartz Tintcoat
- Interior Color
- Jet Black With Kalahari Accents
- Odometer
- 106,879 miles
- Transmission
- 10-Speed Automatic
- Drivetrain
- 4WD
- Engine
- Duramax 6.6L V8 Turbodiesel
- VIN
- 1GT49PEY5LF292681
- Stock Number
- C25SD092B
Included Packages & Accessories
- 6 Speakers
- AM/FM radio: SiriusXM
- Premium audio system: Premium GMC Infotainment System
- Air Conditioning
- Automatic temperature control
- Front dual zone A/C
- Rear window defroster
- Memory seat
- Power driver seat
- Power steering
- Power windows
- Remote keyless entry
- Steering wheel mounted audio controls
- Speed-sensing steering
- Traction control
- 4-Wheel Disc Brakes
- ABS brakes
- Dual front impact airbags
- Dual front side impact airbags
- Front anti-roll bar
- Front wheel independent suspension
- Low tire pressure warning
- Occupant sensing airbag
- Overhead airbag
- Power Sunroof
- Pickup Box
- Brake assist
- Electronic Stability Control
- Lane Departure Warning System
- Delay-off headlights
- Front fog lights
- Fully automatic headlights
- Panic alarm
- Security system
- Speed control
- 220 Amps Alternator
- Engine Block Heater
- Exhaust Brake
- Heavy-Duty 80 Amp Battery
- 6" Rectangular Black Tubular Assist Steps (LPO)
- Auto-dimming door mirrors
- Bumpers: body-color
- Heated door mirrors
- Power door mirrors
- Rear step bumper
- Turn signal indicator mirrors
- Winter Grille Cover
- 2 USB Ports (1st Row)
- Apple CarPlay/Android Auto
- Auto-dimming Rear-View mirror
- Compass
- Driver door bin
- Driver vanity mirror
- Front reading lights
- Heated steering wheel
- Illuminated entry
- Outside temperature display
- Overhead console
- Passenger vanity mirror
- Rear reading lights
- Rear seat center armrest
- Tachometer
- Telescoping steering wheel
- Tilt steering wheel
- Trip computer
- Voltmeter
- Front Center Armrest
- Heated front seats
- Heated rear seats
- Perforated Leather-Appointed Front Seat Trim
- Power passenger seat
- Split folding rear seat
- Ventilated front seats
- Passenger door bin
- Hitch Guidance w/Hitch View
- In-Vehicle Trailering System App
- Trailer Tire Pressure Monitor Sensors
- Alloy wheels
- Wheels: 18" 6-Spoke Machined Aluminum
- Variably intermittent wipers
- 3.42 Axle Ratio
- 3.73 Rear Axle Ratio
- AT4 Preferred Package
- AT4 Premium Package
- Driver Alert Package I
- Driver Alert Package II
- Gooseneck/5th Wheel Package
- Gooseneck/5th Wheel Prep Package
- Preferred Equipment Group 4SB
- Technology Package
- X31 Off-Road Package
- 6-Speaker Audio System Feature
- Bose Premium 7 Speaker Sound System
- HD Radio
- Radio: AM/FM w/Premium GMC Infotainment System
- Radio: Premium GMC Infotainment Sys w/Navigation
- SiriusXM w/360L
- Steering Wheel Audio Controls
- Electric Rear-Window Defogger
- 12-Volt Rear Auxiliary Power Outlet
- 120-Volt Bed Mounted Power Outlet
- 120-Volt Instrument Panel Power Outlet
- Driver Memory
- Power Windows w/Driver Express Up/Down
- Remote Vehicle Starter System
- Universal Home Remote
- Manual Tilt-Wheel/Telescoping Steering Column
- Off-Road Suspension
- Electrical Lock Control Steering Column
- Keyless Open & Start
- Power Door Locks
- Hill Descent Control
- Unauthorized Entry Theft-Deterrent System
- 2-Speed Active Transfer Case
- IntelliBeam Automatic High Beam On/Off
- LED Cargo Area Lighting
- LED Smoked Amber Roof Marker Lamps
- Painted Black Surround Grille
- Rear Wheelhouse Liners
- Spray-On Pickup Box Bed Liner w/AT4 Logo
- 2 USB Ports
- 2nd Row Dual USB Charge-Only Ports
- 4.2" Diagonal Color Display Driver Info Center
- 4G LTE Wi-Fi Hotspot Capable
- 8" Multicolor Driver Instrument Info Display
- Automatic Emergency Braking
- Bed View Camera
- Compass Located In Instrument Cluster
- Floor-Mounted Center Console
- Following Distance Indicator
- Forward Collision Alert
- GMC Connected Access Capable
- HD Rear Vision Camera
- HD Surround Vision w/2 Trailer View Camera Provisions
- Lane Change Alert w/Side Blind Zone Alert
- Multicolor 15" Diagonal Head-Up Display
- OnStar & GMC Connected Services Capable
- Rear Camera Mirror
- Rear Cross Traffic Alert
- Ultrasonic Front & Rear Park Assist
- Wireless Charging
- 10-Way Power Driver Seat Adjuster w/Lumbar
- 10-Way Power Passenger Seat Adjuster w/Lumbar
- Front Bucket Seats
- Heated & Ventilated Front Bucket Seats
- Heated 2nd Row Outboard Seats
- Heated Driver & Front Outboard Passenger Seats
- Safety Alert Seat
- Integrated Trailer Brake Controller
- Wheels: 20" 6-Spoke Bright Machined Aluminum
- Deep-Tinted Glass
- Power Front Passenger Windows w/Express Up/Down
- Power Rear Windows w/Express Down
- Power Sliding Rear Window w/Defogger
Detailed Specifications
- 1st and 2nd row curtain head airbags
- 4-wheel ABS Brakes
- ABS and Driveline Traction Control
- Aluminum dash trim
- Aluminum/sim carbon fibre center console trim
- Aluminum/sim carbon fibre door trim
- Anti-theft alarm system
- Audio System Premium Brand : Premium GMC Infotainment System
- Audio controls on steering wheel
- Audio system memory card slot
- Automatic front air conditioning
- Auxilliary engine cooler
- Auxilliary transmission cooler
- Bluetooth wireless phone connectivity
- Braking Assist
- Bucket front seats
- Climate Controlled : Driver and passenger heated
- Compass
- Cruise control
- Cruise controls on steering wheel
- Daytime running lights
- Digital Audio Input
- Driver seat memory
- Dual front air conditioning zones
- Dual illuminated vanity mirrors
- Electrochromatic auto-dimming mirrors
- Electrochromatic rearview mirror
- External temperature display
- Fold-up cushion rear seats
- Front Ventilated disc brakes
- Front and rear reading lights
- Front fog/driving lights
- Heated driver mirror
- Heated passenger mirror
- Heated steering wheel
- Leather seat upholstery
- Leather/aluminum steering wheel trim
- Machined aluminum rims w/ painted accents
- Memorized Settings for 2 drivers
- Memorized Settings including door mirror(s)
- Passenger Airbag
- Power extendable trailer style exterior mirrors
- Power remote driver mirror adjustment
- Power remote passenger mirror adjustment
- Power retractable mirrors
- Power windows
- Privacy glass: Deep
- Rear seats center armrest
- Remote Engine Start : Keyfob remote start
- Remote activated exterior entry lights
- Remote power door locks
- Remote window operation
- Side airbag
- SiriusXM AM/FM/HD/Satellite Radio
- SiriusXM Satellite Radio(TM)
- Speed-proportional power steering
- Split rear bench
- Stability controll with anti-roll
- Suspension class: Off-road
- Tachometer
- Tilt and telescopic steering wheel
- Tire Pressure Monitoring System: Tire specific
- Total Number of Speakers: 6
- Trailer hitch
- Trip computer
- Turn signal in mirrors
- Urethane shift knob trim
- Video Monitor Location: Front
- Wheel Diameter: 18
- Wheel Width: 8
Dealer Notes
KBB.com Consumer Reviews
- 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 - 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! - 3.0
Don't judge a truck by the appearance
By jmil on Wednesday, May 11, 2022
Great truck, loved it until the DEF tank heater malfunctioned and shut down the truck. Now sitting waiting for the replacement tank for over 10 weeks. Turns out every HD truck 2020 and 2021 has the same problem and all will need this replacement that is being produced at a snail's pace by GM. Per the dealership, last count, over 9000 trucks like mine are idle waiting for this part. $65000 waste of money and terrible service by GMC (not the local dealership).
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