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1620 East Homer Adams Pkwy Alton, IL 62002

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2020 GMC Sierra 3500HD AT4 OVERVIEW Overview Icon

2020 GMC Sierra 3500HD AT4 in Alton

DISTINCTLY RUGGED

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  • Maximum conventional trailering capacity of up to 20,000lbs
  • GMC MultiPro Tailgate
  • Autotrac® 2-speed transfer case with push button controls
  • Cargo bed LED lighting
  • HD Rear Vision Camera
2020 GMC Sierra 3500HD AT4 Main Img

2020 GMC Sierra 3500HD AT4 MODELS

  • Sierra 3500HD AT4

    Sierra 3500HD AT4

  • Sierra 3500HD AT4 Single Rear Wheel Denali

    Sierra 3500HD AT4 Single Rear Wheel Denali

2020 GMC Sierra 3500HD AT4 CONFIGURATIONS

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

GMC Sierra 3500HD AT4 Dealer in Alton

2020 GMC Sierra 3500HD AT4 PERFORMANCE Performance Icon

2020 GMC Sierra 3500HD AT4 performance

All-New 6.6L V8 Gas Engine

  • 401 hp
  • 464 lb-ft of torque
  • Compression Ratio of 10.75:1
  • Valve Train: overhead-valve, two valves per cylinder, variable valve timing
2020 GMC Sierra 3500HD AT4 performance

Available 6.6L Duramax Turbo Diesel V8

  • 445 hp
  • 910 lb-ft of torque
  • Compression Ratio of 16:1
  • Diesel Exhaust Brake System
  • Valve Train: overhead-valve, four valves per cylinder
  • Paired with the Allison® 10-Speed Automatic Transmission
2020 GMC Sierra 3500HD AT4 performance

Auto Electric Parking Brake

To help with positioning, after backing up to a trailer hitch using Hitch View1, Sierra AT4 Heavy Duty will automatically apply the parking brake upon shifting into park to avoid unintentional rolling.

2020 GMC Sierra 3500HD AT4 performance

Available Gooseneck/Fifth-Wheel Prep Package

  • Hitch platform to accept gooseneck or fifth-wheel hitch
  • Hitch platform with tray to accept ball and stamped bed holes with removable caps installed
  • Bed-mounted 7-pin trailer harness
  • Bed View camera1 with two wiring provisions for available accessory cameras

2020 GMC Sierra 3500HD AT4 APPEARANCE Appearance Icon

Best-in-Class Heavy-Duty Cargo Bed Volume Inner Gate With Work Surface 2020 GMC Sierra 3500HD AT4 Appearance Main Img
2020 GMC Sierra 3500HD AT4 appearance

Best-in-Class Heavy-Duty Cargo Bed Volume

Roll-formed high-strength steel bed

Durable spray-on bedliner with AT4 logo

12 cargo tie-downs (500-lb rating per corner)

Best-in-class heavy-duty cargo bed volume:
Standard Bed: 69.6 cu. ft.
-Long Bed: 83.5 cu. ft.

2020 GMC Sierra 3500HD AT4 appearance

Inner Gate With Work Surface

The opened inner gate provides a work surface as well as second-tier loading.

2020 GMC Sierra 3500HD AT4 COMFORT Comfort Icon

2020 GMC Sierra 3500HD AT4 comfort

Available Multicolor 15" Diagonal Head-Up Display

A multicolor 15" diagonal Head-Up Display, the first in a heavy-duty pickup, helps you keep your eyes on the road by conveniently projecting key information directly onto the windshield 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
2020 GMC Sierra 3500HD AT4 comfort

Smart Trailer Integration

Sierra AT4 Heavy Duty is being designed to integrate ASA Electronics' iN∙Command® Control System with Global Connect1 and accessed through the myGMC mobile app.2 The system allows owners to monitor and control a range of smart systems, such as water tank levels, HVAC controls and even power slide-outs, in recreational trailers equipped with the technology.

2020 GMC Sierra 3500HD AT4 comfort

Rear Seatback and Available Under-Seat Storage

Convenient storage solutions are found inside the rear outboard seatbacks and underneath the rear seats.

2020 GMC Sierra 3500HD AT4 comfort

Exclusive All-Weather Floor Liners

Durable all-weather floor liners help protect your vehicle’s floors from dirt and debris.

2020 GMC Sierra 3500HD 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
2020 GMC Sierra 3500HD AT4 Safety Main Img
2020 GMC Sierra 3500HD AT4 safety

Automatic Emergency Braking

Automatic Emergency Braking operates below 50 mph, and can alert you when it detects a front-end collision is imminent with a vehicle ahead you are following. It also can help reduce the collision’s severity or avoid the collision by automatically applying hard emergency braking if you have not already, or by enhancing driver hard braking.

2020 GMC Sierra 3500HD AT4 safety

Lane Departure Warning

Lane Departure Warning can provide alerts to help you avoid crashes due to unintentionally drifting out of your lane when your turn signal is not activated.

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