Mildenberger Motors

1717 N First Street Hamilton, MT 59840

2021 GMC Sierra 3500 AT4 OVERVIEW Overview Icon

2021 GMC Sierra 3500 AT4 in Hamilton

  • 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 Main Img

2021 GMC Sierra 3500 AT4 CONFIGURATIONS

* Model and trim configurations may vary
  • Sierra 3500 AT4 Crew Cab Standard Bed
    Sierra 3500 AT4 Crew Cab Standard Bed
  • Sierra 3500 AT4 Crew Cab Long Bed
    Sierra 3500 AT4 Crew Cab Long Bed

GMC Sierra 3500 AT4 Dealer in Hamilton

2021 GMC Sierra 3500 AT4 PERFORMANCE Performance Icon

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
2021 GMC Sierra 3500 AT4 performance

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
2021 GMC Sierra 3500 AT4 performance

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 Appearance Icon

2021 GMC Sierra 3500 AT4 Appearance Main Img
2021 GMC Sierra 3500 AT4 appearance

AVAILABLE AT4 HIGH CLEARANCE STEP

2021 GMC Sierra 3500 AT4 appearance

EXCLUSIVE EXTERIOR STYLINGS

2021 GMC Sierra 3500 AT4 appearance

VERTICAL RED RECOVERY HOOKS

2021 GMC Sierra 3500 AT4 COMFORT Comfort Icon

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
2021 GMC Sierra 3500 AT4 comfort

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.

2021 GMC Sierra 3500 AT4 comfort

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
2021 GMC Sierra 3500 AT4 comfort

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 Safety Icon

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
2021 GMC Sierra 3500 AT4 Safety Main Img
2021 GMC Sierra 3500 AT4 safety

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.

2021 GMC Sierra 3500 AT4 safety

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.

2021 GMC Sierra 3500 AT4 safety

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.

We're sorry, but we do not have a 2021 GMC Sierra 3500 AT4 in our current inventory.

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