Quality Buick GMC

1620 East Homer Adams Pkwy Alton, IL 62002

2020 GMC Sierra 1500 AT4 OVERVIEW Overview Icon

2020 GMC Sierra 1500 AT4 in Alton

  • 2" Lift with off-road suspension and shocks
  • 420 max. horsepower2, 460 lb.-ft. max. torque2, 9,800 lbs. max. towing3
  • 22 city/ 26 hwy est. MPG with available 3.0L turbo diesel4
  • Distinct exterior design with black chrome accents
2020 GMC Sierra 1500 AT4 Main Img


* Model and trim configurations may vary
  • Sierra 1500 AT4 Crew Cab Short Box
    Sierra 1500 AT4 Crew Cab Short Box
  • Sierra 1500 AT4 Crew Cab Standard Box
    Sierra 1500 AT4 Crew Cab Standard Box
  • Sierra 1500 AT4 Double Cab Standard Box
    Sierra 1500 AT4 Double Cab Standard Box

GMC Sierra 1500 AT4 Dealer in Alton

2020 GMC Sierra 1500 AT4 PERFORMANCE Performance Icon

2020 GMC Sierra 1500 AT4 performance

2" Lift with Off-Road Suspension and Shocks

The factory-installed 2-inch suspension lift gives you the ground clearance you want when heading off-road, while Rancho® monotube shock absorbers are off-road tuned to help smooth out rough terrain.

2020 GMC Sierra 1500 AT4 performance

Capability Without Compromise

  • An automatic locking rear differential helps maneuver out of deep terrain
  • Skid plates offer added protection up front and under body
  • Hill Descent Control is activated by a push of a button on the instrument panel, uses antilock braking to help provide a smooth, controlled descent in rough terrain 
2020 GMC Sierra 1500 AT4 performance

Adapt to the Road Conditions

Sierra AT4 pickup truck comes standard with four-wheel drive and a 2-speed AutoTrac transfer case that includes low-range four-wheel-drive gearing that handles a variety of off-road conditions.

2020 GMC Sierra 1500 AT4 performance

Traction Select System

The Traction Select System on the Sierra AT4 allows the driver to choose from preset drive modes that have been tailored for different terrain or weather conditions. It adjusts Sierra's transmission shift points, throttle mapping and StabiliTrak to optimize performance for the situation. The available modes in the Traction Select System are:

  • Tour
  • Sport
  • Off-Road
  • Tow/Haul

Learn more about Sierra AT4's Traction Select System on GMC LIFE.

2020 GMC Sierra 1500 AT4 performance

Dynamic Fuel Management

Included with the 5.3L V8 and available 6.2L V8, the Dynamic Fuel Management system enables the engine to operate in 17 different patterns between 2 and 8 cylinders, depending on demand, to optimize power delivery and efficiency.

2020 GMC Sierra 1500 AT4 performance

Strong, Capable Cargo Box

This cargo box accommodates your active lifestyle with the functionality and strength to load and haul heavy toys and cargo. Cargo bed capabilities include:

  • More cargo bed volume than any competitor, from 62.9 to 71.7 cu. ft.5
  • Durable, high-strength, roll-formed steel bed
  • World's First Six-Function MultiPro™ Tailgate, offers a fold-out step for easy access to the bed
  • 12 total cargo tie-downs – rated up to 500 lbs per corner6
  • Rear and side task lighting
  • 120V electrical outlet in the bed
  • CornerStep footwells in the rear bumper

2020 GMC Sierra 1500 AT4 APPEARANCE Appearance Icon

2020 GMC Sierra 1500 AT4 Appearance Main Img
2020 GMC Sierra 1500 AT4 appearance

Dark, Distinguished Appearance

The Sierra AT4's unique design elements include:

  • Grille insert with finished in black chrome
  • Black chrome fog lamp surrounds
  • Vertical red recovery hooks7
  • Black side window surround
  • Body-color grille surround, door handles and bumpers
  • Unique AT4 badging
2020 GMC Sierra 1500 AT4 appearance

High-Intensity LED Headlamps

Style and function combine in Sierra AT4 off-road pickup truck's signature high-intensity LED headlamps with unique C-shape lighting, LED taillamps and LED fog lamps and light blade technology gives headlamps and taillamps a premium look.

2020 GMC Sierra 1500 AT4 appearance

Integrated Dual Exhaust

Bright, polished dual exhaust outlets stand out below the body-color rear bumper creating a clean design that adds to Sierra AT4's premium appearance.

2020 GMC Sierra 1500 AT4 appearance

Off-Road Tires and Exclusive Wheels

GMC Sierra AT4 truck is equipped to leave pavement behind with aggressive, all-terrain tires and exclusive wheels:

  • Available mud terrain-rated Goodyear® Wrangler DuraTrac® tires
  • Unique 18" 6-spoke machined aluminum wheels with dark grey accents
  • Available 20" machined aluminum wheels with Carbon Grey Metallic accents
  • New available 20" 6-spoke Carbon Grey painted aluminum wheels (requires AT4 CarbonPro Edition)

2020 GMC Sierra 1500 AT4 COMFORT Comfort Icon

2020 GMC Sierra 1500 AT4 comfort

Distinctive Style

The interior is just as bold as the exterior with darkened, premium features that include:

  • Unique Jet Black interior with Kalahari accents
  • Dark-finish technical aluminum detail
  • Heated front seats with leather appointments
  • Embroidered AT4 badging on the front head restraints
  • New All-weather floor liners, 1st and 2nd rows (includes AT4 logo)
2020 GMC Sierra 1500 AT4 comfort

Storage Space

Space is used wisely with well-placed compartments for storing and securing your items including:

  • Rear seatback storage includes two compartments inside the rear outboard seatbacks, perfect for stowing tablets, charge cords and small outdoor gear
  • Open storage tray on the instrument panel, great place for phone storage
  • Rear underseat storage bin
  • Lighted center console storage with available lockable console vault accessory8
  • Large lower lockable glove box and upper glove box
  • Rear-seat center cupholders
2020 GMC Sierra 1500 AT4 comfort

Class-Leading Crew Cab Front Head and Leg Room (max)9

Outside, the stance is bold, and inside the large proportions help give you the added confidence of sitting high. You can also stretch out with class-leading max front head and leg room in the Sierra AT4 Crew Cab.

2020 GMC Sierra 1500 AT4 comfort

Rear-Seat Passenger Comfort

Larger rear-door openings and more rear-seat leg room than the previous generation. Sierra pick truck models make your passengers feel comfortable with rear vents and heated rear outboard seats keep them that way for the long haul.

2020 GMC Sierra 1500 AT4 SAFETY & WARRANTY Safety Icon


Standard on every new GMC - GMC Pro Grade Protection has you truly protected with features and services including:

  • 3-year / 36,000-mile Bumper-to-Bumper Limited Warranty
  • 5-year / 60,000-mile Powertrain Limited Warranty
  • 5-year / 60,000-mile Roadside Assistance & Courtesy Transportation
  • 3-year / 36,000-mile Corrosion Protection
  • 6-year / 100,000-mile Rust-Through Protection
  • First maintenance visit
2020 GMC Sierra 1500 AT4 Safety Main Img
2020 GMC Sierra 1500 AT4 safety

Game-Changing Technology

Venture off-road in the powerfully capable Sierra AT4 pickup truck with the added confidence of available technology features designed with the driver in mind:

  • Available first-in-class multicolor Head-Up Display shows you key information low on the windshield, like an Off-Road Inclinometer that shows the fore-and-aft tilt, front tire angle, and left-and-right tilt
  • Available first-in-class Rear Camera Mirror10 turns your rearview mirror into a camera feed to help you see the terrain behind you
  • Up to 15 different camera views available in the Technology Package, which includes HD Surround Vision10, Rear Camera Mirror10 and Bed View Camera11
  • Available 8" Digital Driver Information Center lets you access the vehicle information you want to see
2020 GMC Sierra 1500 AT4 safety

Advanced Safety and Driver Assistance

GMC Sierra AT4 pickup truck offers advanced safety features and intelligent driver-centric alerts that can help alert you to potential hazards.10

The following features are available:

  • IntelliBeam Headlamps
  • Adaptive Cruise Control – Camera
  • Lane Change Alert with Side Blind Zone Alert
  • Forward Collision Alert
  • Lane Keep Assist with Lane Departure Warning
  • Following Distance Indicator
  • Front Pedestrian Braking
  • Rear Cross Traffic Alert
  • Safety Alert Seat
  • Automatic Emergency Braking
  • Front and Rear Park Assist
  1. The Manufacturer's Suggested Retail Price excludes destination freight charge, tax, title, license, dealer fees and optional equipment. See your GMC dealer for details.
  2. Requires available 6.2L V-8 engine.
  3. Requires Crew Cab short box with 5.3L V-8 engine. Before you buy a vehicle or use it for trailering, carefully review the trailering section of the Owner's Manual. The weight of passengers, cargo and options or accessories may reduce the amount you can tow.
  4. 16 city/ 21 hwy with 5.3L V8, 15 city/ 19 hwy with available 6.2L V8, 22 city/ 26 hwy with available 3.0L Turbo Diesel - EPA Estimates
  5. Steel bed measurements. Cargo and load capacity limited by weight and distribution.
  6. Cargo and load capacity limited by weight and distribution.
  7. To avoid the risk of injury, never use recovery hooks to tow a vehicle. For more information, see your Owner's Manual.
  8. Requires dealer installation.
  9. Based on GM Half-Ton Pickup Segment. Excludes other GM vehicles.
  10. Safety or driver-assistance features are no substitute for the driver's responsibility to operate the vehicle in a safe manner. The driver should remain attentive to traffic, surroundings and road conditions at all times. Visibility, weather and road conditions may affect feature performance. Read the vehicle Owner's Manual for more important feature limitations and information.
  11. Read the vehicle Owner's Manual for important feature limitations and information. Some camera views require available accessory camera and installation. Not compatible with all trailers. See your dealer for details.

We're sorry, but we do not have a 2020 GMC Sierra 1500 AT4 in our current inventory.

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