2021 GMC Sierra 3500 AT4
2021 GMC Sierra 3500 AT4 OVERVIEW 
2021 GMC Sierra 3500 AT4 For Sale
- Off-road suspension, Rancho shocks and skid plates
- 18" all-terrain tires and available 20" all-terrain tires
- Exclusive Jet Black interior with Kalahari accents
- Available Lane Departure Warning
2021 GMC Sierra 3500 AT4 CONFIGURATIONS
* Model and trim configurations may vary
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Sierra 3500 AT4 Crew Cab Standard Bed
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Sierra 3500 AT4 Crew Cab Long Bed
GMC Sierra 3500 AT4 For Sale
2021 GMC Sierra 3500 AT4 PERFORMANCE 
RESPONSIVE SUSPENSIONS
- AT4 & Denali’s independent front suspensions provide excellent wheel alignment, ride comfort and turnability with reduced weight
- Live-axle suspension includes two-stage, semielliptic multileaf rear springs to balance payload management and ride quality
MADE FOR OFF-ROAD
- First HD in its class to offer a 2-speed AutoTrac transfer case with an active automatic 4WD drive setting which provides seamless shifting between two- and four-wheel drive based on road conditions
- Hill Descent Control
- Skid plates provide added underbody protection
- Equipped with Off-Road Mode
- Standard 18" machined aluminum wheels with Dark Grey metallic accents with standard All Terrain blackwall tires and available mud terrain tires
- Available 20" machined aluminum wheels with high-gloss black accents with All Terrain black wall tires
NEXT-LEVEL GROUND CLEARANCE
To assist in clearing rugged terrain, available Sierra HD AT4 offers up to 11.18" of ground clearance along with a maximum approach angle of 27 degrees.
2021 GMC Sierra 3500 AT4 APPEARANCE 
AVAILABLE AT4 HIGH CLEARANCE STEP
EXCLUSIVE EXTERIOR STYLINGS
VERTICAL RED RECOVERY HOOKS
2021 GMC Sierra 3500 AT4 COMFORT 
BEST-IN-CLASS HEAVY DUTY CARGO BED VOLUME
- Roll-formed high-strength steel bed
- Best-in-class heavy-duty cargo box volume
- Standard Bed: 69.6 cu. ft.
- Long Bed: 83.5 cu. ft.
- 12 cargo tie-downs (500-lb. rating per corner)
- LED Lighting
- Available durable spray-on bedliner
SMART REAR SEAT STORAGE
Convenient and spacious storage solutions include available rear seatback storage, perfect for stowing a smartphone and your other road trip essentials.
AVAILABLE FIRST-IN-CLASS 15” DIAGONAL HEAD-UP DISPLAY
A multicolor 15" diagonal Head-Up Display (a first in the heavy-duty pickup class) helps you keep your eyes on the road by projecting directly onto the windshield key information such as:
- Speed
- Tachometer
- Audio
- Phone
- Available Navigation
- Forward Collision Alert
- Lane Departure Warning
- Cruise Control
- Low Fuel
- Off-road inclinometer that measures fore-and-aft tilt, front tire angle and left-and-right tilt
MULTIPRO AUDIO SYSTEM BY KICKER®
When you’re camping or tailgating and want to bring your music outdoors – without leaving your truck running – the available accessory MultiPro Audio System by Kicker is designed to integrate into the MultiPro™ Tailgate. This 100-watt exterior audio system has full Bluetooth® streaming capability.
2021 GMC Sierra 3500 AT4 SAFETY & WARRANTY 
PRO GRADE PROTECTION
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
AVAILABLE LANE DEPARTURE WARNING
Uses a brief, gentle steering wheel turn to alert you when you may be unintentionally drifting out of detected lane lines, so you can steer to stay safely in your lane. If needed, you may receive additional Lane Departure Warning alerts. System alerts do not occur if you’re using your turn signal or it detects that you are intentionally leaving your lane. Available on SLE, SLT and AT4. Standard on Denali.
AVAILABLE FRONT AND REAR PARK ASSIST
Front and Rear Park Assist provides distance alerts to nearby detected objects to help you park and avoid objects at low speeds. Available on base Sierra HD, SLE, SLT and AT4. Standard on Denali.
AVAILABLE FORWARD COLLISION ALERT
Forward Collision Alert can warn you if it detects a potential front-end collision with a vehicle you're following so you can quickly take action. The system can also provide a tailgating alert if you are following a vehicle much too closely. Available on base Sierra HD, SLE, SLT and AT4. Standard on Denali.