Mildenberger Motors

1717 N First Street Hamilton, MT 59840

2021 GMC Sierra 1500 AT4 OVERVIEW Overview Icon

2021 GMC Sierra 1500 AT4 in Hamilton

  • 5.3L EcoTec3 V8 engine with DFM
  • 355 hp [265 kW] @ 5600 rpm
  • Premium GMC Infotainment System with customizable profiles and 8" diagonal touchscreen
  • Blind Zone Alert
2021 GMC Sierra 1500 AT4 Main Img

2021 GMC Sierra 1500 AT4 CONFIGURATIONS

* Model and trim configurations may vary
  • Sierra 1500 AT4 Double Cab Standard Box
    Sierra 1500 AT4 Double Cab Standard Box
  • 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 Regular Cab Long Box
    Sierra 1500 AT4 Regular Cab Long Box

GMC Sierra 1500 AT4 Dealer in Hamilton

2021 GMC Sierra 1500 AT4 PERFORMANCE Performance Icon

2021 GMC Sierra 1500 AT4 performance

FIRST-CLASS CAPABILITY

  • Factory-installed 2-inch suspension lift gives AT4 its outstanding ground clearance
  • Rancho® shock absorbers helps deliver the smooth ride you want when heading off-road
  • Available Duramax® 3.0L Turbo-Diesel engine or 6.2L EcoTec®3 V8 engine
  • Available 18" Mud-Terrain Goodyear Wrangler DuraTrac® tires and 20" Mud-Terrain Goodyear Wrangler DuraTrac® Territory tire options
2021 GMC Sierra 1500 AT4 performance

TRACTION SELECT SYSTEM

Traction Select System 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
  • Terrain (available on 4WD models with single-speed transfer case)
  • Snow (2WD models only)
  • Tow/Haul
  • Off Road
2021 GMC Sierra 1500 AT4 performance

QUIETER PERFORMANCE

The 3.0L Duramax was designed to be a ‘no-excuses’ engine option that not only offers excellent efficiency, but a much quieter and smoother driving experience thanks to its inline-six (I-6) architecture.

2021 GMC Sierra 1500 AT4 APPEARANCE Appearance Icon

2021 GMC Sierra 1500 AT4 Appearance Main Img
2021 GMC Sierra 1500 AT4 appearance

2" FACTORY INSTALLED SUSPENSION LIFT

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

2021 GMC Sierra 1500 AT4 appearance

POLISHED DUAL EXHAUST OUTLETS

Bright, polished dual exhaust outlets are seamlessly integrated into Sierra’s rear bumper design, creating a sleek, sophisticated look that enhances its premium appearance. Standard on AT4 and Denali. Available on SLE, Elevation and SLT.

2021 GMC Sierra 1500 AT4 appearance

VERTICAL RED RECOVERY HOOKS

Sierra AT4’s vertical red Recovery Hooks add distinction to the front bumper and are perfect for pulling another vehicle out of a recovery situation.

2021 GMC Sierra 1500 AT4 appearance

EXCLUSIVE AT4 OFF-ROAD TIRES

GMC Sierra AT4 truck is equipped to leave pavement behind with aggressive, mud-terrain tires:

  • Available 18" mud-terrain Goodyear® Wrangler DuraTrac® tires
  • Available 20" mud-terrain Goodyear Wrangler Territory tires

2021 GMC Sierra 1500 AT4 COMFORT Comfort Icon

2021 GMC Sierra 1500 AT4 comfort

AVAILABLE ACCESSORY MULTIPRO AUDIO SYSTEM BY KICKER®

Take your music outdoors while camping or tailgating with the MultiPro Tailgate integrated with the available accessory MultiPro Audio System by Kicker®. This 100-watt exterior audio system has full Bluetooth® streaming capability and enough power to keep the party going – without leaving your Sierra running.
Available on SLE, Elevation, SLT, AT4 and Denali. Standard on Denali and AT4 CarbonPro Editions.

2021 GMC Sierra 1500 AT4 comfort

WIRELESS CHARGING

When on the road in the Sierra 1500, it’s OK to leave the cords at home. The available wireless charging pad, located within easy reach near the cupholders, has excellent charging abilities and keeps your compatible smartphone charged and ready. Available on SLT and AT4. Standard on Denali.

2021 GMC Sierra 1500 AT4 comfort

DISTINCTIVE DETAILS

  • Standard 10-way power-adjustable bucket seats with center console
  • Heated and ventilated, perforated front leather seating surfaces
  • Unique Jet Black interior with Kalahari accents
  • Dark-finish technical aluminum detail
  • Embroidered AT4 badging on the front head restraints
  • Premium front and rear floor liners with removable carpet inserts
2021 GMC Sierra 1500 AT4 comfort

IN-VEHICLE TRAILERING APP

To help improve your trailering experience, Sierra’s available In-Vehicle Trailering App offers custom trailer profiles, trailer statuses including available tire pressure and temperature monitoring and more. The app is integrated and accessible through Sierra’s Infotainment System, with features including:

  • Create 5 custom trailer profiles based on trailer name, trailer type, trailer hitch type
  • Phone companion app, myGMC Mobile App adding convenience when outside the truck or trailer
  • Trailer tire pressure monitoring system that measures pressure and temperature (requires Trailer Pressure Monitor Sensors)
  • Trailer Light Sequence, which includes automatic lighting test sequence
  • Maintenance reminders
  • Step-by-step pre-departure checklists
  • Track trailer mileage and fuel economy

Available on SLE and Elevation. Standard on SLT, AT4 and Denali.

2021 GMC Sierra 1500 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 1500 AT4 Safety Main Img
2021 GMC Sierra 1500 AT4 safety

AVAILABLE REAR CROSS TRAFFIC ALERT

Rear Cross Traffic Alert can warn you of detected left- or right-cross traffic behind your vehicle when you’re in Reverse.

2021 GMC Sierra 1500 AT4 safety

AVAILABLE LANE CHANGE ALERT WITH SIDE BLIND ZONE ALERT

Lane Change Alert with Side Blind Zone Alert can provide side-mirror visual alerts when a detected moving vehicle is quickly approaching or is in your side blind zone.

2021 GMC Sierra 1500 AT4 safety

AVAILABLE FRONT PEDESTRIAN BRAKING

Front Pedestrian Braking can help you avoid or reduce the severity of a front-end collision with a pedestrian it detects directly ahead of you. It provides pedestrian alerts and can even automatically provide hard emergency braking or enhance the driver’s hard braking. The system works at speeds below 50 MPH during the daytime. It has limited nighttime and low visibility performance.

We're sorry, but we do not have a 2021 GMC Sierra 1500 AT4 in our current inventory.

Search for New Vehicles | Search for Used Vehicles

Disclaimers