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1620 East Homer Adams Pkwy Alton, IL 62002

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2021 GMC Sierra 3500HD Denali OVERVIEW Overview Icon

2021 GMC Sierra 3500HD Denali in Alton

Get Current Pricing*
  • Max conventional trailering capacity of up to 20,000 lbs*
  • Max fifth-wheel/gooseneck rating of up to 30,990 lbs*
  • Max payload of up to 6,374 lbs*
  • 69.6–83.5 cu.ft. cargo volume
2021 GMC Sierra 3500HD Denali Main Img

2021 GMC Sierra 3500HD Denali CONFIGURATIONS

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

GMC Sierra 3500HD Denali Dealer in Alton

2021 GMC Sierra 3500HD Denali PERFORMANCE Performance Icon

2021 GMC Sierra 3500HD Denali performance

AVAILABLE 6.6L DURAMAX® TURBO-DIESEL V8 ENGINE

  • 445 hp and 910 lb.-ft. of torque
  • Larger variable-speed cooling fan and dual path air induction system 
  • Factory-installed diesel after-run function maintains an ideal temperature for performance and minimize fuel consumption
  • Intelligent diesel exhaust brake system
  • Large rear axle ring gears (11.5" on 2500, 12" on 3500) allow for all-around mix of engine performance, towing strength, and efficiency
2021 GMC Sierra 3500HD Denali performance

AVAILABLE ALLISON® 10-SPEED AUTOMATIC TRANSMISSION

  • First HD in its class with Allison 10-speed automatic transmission
  • Developed specifically for Sierra Heavy Duty
  • Optimizes gear shifts for maximum power, torque and efficiency
  • Closer gear spacing that allows the engine to operate in an optimal range at all times with varying load and terrain conditions
2021 GMC Sierra 3500HD Denali performance

HIGH-STRENGTH CHASSIS AND SUSPENSION

The strong chassis, suspension and wheelbase (standard/long: 158.94"/172") are built upon a fully boxed, ladder-type frame built from high-strength steel using front hydroformed rails with clamshell design. The optimized frame and body structure works in conjunction with larger driveline components that feature high-strength axles featuring larger ring gears (11.5" on 2500, 12" on 3500) to bring immediate torque to ground for increased power while towing and off-roading.

2021 GMC Sierra 3500HD Denali performance

OPTIMAL ENGINE PERFORMANCE

To help maintain optimal operating temperatures of the available 6.6L Duramax® Turbo Diesel V8 engine, a massive 28" variable-speed cooling fan was added. Dense, cool air from the Dual Path Air Induction System is drawn through both the hood scoop and the large grille to maximize horsepower and help optimize trailering performance. The factory-installed Diesel After-Run feature is designed to help cool down the engine following heavy usage

2021 GMC Sierra 3500HD Denali APPEARANCE Appearance Icon

2021 GMC Sierra 3500HD Denali Appearance Main Img
2021 GMC Sierra 3500HD Denali appearance

MULTIPRO TAILGATE WITH PUSH BUTTON PANEL AND HITCH AREA LIGHT

2021 GMC Sierra 3500HD Denali appearance

SIGNATURE DENALI GRILLE WITH CHROME INSERTS

2021 GMC Sierra 3500HD Denali appearance

CHROME 6" ASSIST STEPS

2021 GMC Sierra 3500HD Denali appearance

CHROME VERTICAL FRONT RECOVERY HOOKS*, CHROME HANDLES AND CHROME MIRROR CAPS

2021 GMC Sierra 3500HD Denali appearance

DUAL-PATH AIR INDUCTION SYSTEM WITH 6.6 DURAMAX® DIESEL V8 ENGINE

2021 GMC Sierra 3500HD Denali appearance

STANDARD 20" MULTI-DIMENSIONAL POLISHED ALUMINUM WHEELS

2021 GMC Sierra 3500HD Denali COMFORT Comfort Icon

2021 GMC Sierra 3500HD Denali comfort

PREMIUM DENALI FEATURES

  • Denali Exclusive Jet Black or Dark Walnut/Dark Ash Grey interiors
  • Forge perforated leather seating surfaces with heated and ventilated bucket seats (driver seat includes memory)
  • Denali-exclusive authentic Open-Pore Ash Wood, brushed aluminum trim, chrome accents and more
  • Heated rear outboard seating with expansive rear leg room
2021 GMC Sierra 3500HD Denali comfort

Jet Black Perforated Leather Seating Surfaces

GMC Sierra HD Denali Crew Cab Full Interior Overhead View Shown.

2021 GMC Sierra 3500HD Denali comfort

Dark Walnut/Dark Ash Grey Forge Perforated Leather Seating Surfaces

GMC Sierra HD Denali Crew Cab Full Interior Overhead View Shown.

2021 GMC Sierra 3500HD Denali 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 3500HD Denali Safety Main Img
2021 GMC Sierra 3500HD Denali safety

ENHANCED BRAKING CAPABILITY

Brake enhancements include extended-hold Hill Start Assist, which provides extra time to start uphill from a complete stop. Denali also has an innovative Brake Pad Life Monitor and an Electric Parking Brake, which includes Steep Grade Apply and Park Grade Hold Assist to help when driving or parking on steep grades.

2021 GMC Sierra 3500HD Denali safety

TECHNOLOGY TO TOW SMART

Available technologies such as the class-leading available up to 15 camera views* and 15" diagonal Head-Up Display let Denali drivers tow smarter, not harder.

2021 GMC Sierra 3500HD Denali safety

INTELLIBEAM®

When driving conditions are dark, available IntelliBeam auto high beams can automatically turn the vehicle's high-beam headlamps on and off according to surrounding traffic conditions. Standard on Denali.

2021 GMC Sierra 3500HD Denali safety

Safety Alert Seat

Safety Alert Seat* uses left, right, or both-side driver seat vibration pulses to help you identify the direction of potential crashes so you can quickly take action. You can also switch to beeping crash avoidance alerts. Standard on Denali.

2021 GMC Sierra 3500HD Denali safety

ADVANCED SAFETY ALERTS

These safety features are standard on 3500HD Denali.

  • Following Distance Indicator
  • Forward Collision Alert
  • Lane Change Alert with Side Blind Zone Alert
  • Rear Cross Traffic Alert
2021 GMC Sierra 3500HD Denali safety

REAR SIDE VIEW ENHANCEMENTS

  • Provides a line of sight down either side of the truck. When a compatible trailer is connected, you'll see a split view of the left and right sides of the truck and trailer
  • While driving in reverse with a trailer, the view automatically biases based on the trailer's angle
  • When enabled and driving forward with the turn signal activated, a Trailer Length Indicator when enabled and driving forward with the turn signal activated, the center console screen displays a red overlay twice the length of the compatible trailer, showing when other vehicles are present and may interfere with your lane-change maneuver
2021 GMC Sierra 3500HD Denali safety

AVAILABLE JACKKNIFE ALERT*

  • Tracks the position of the compatible trailer in relation to the vehicle and if the front of the trailer approaches the rear of the vehicle, an alert is displayed that you're in a potential jackknife situation
  • A yellow warning alert will be displayed when truck/trailer angle is 75% into a jackknife scenario
  • A red warning alert will be displayed when truck/trailer angle is 90% into a jackknife scenario (i.e., collision is imminent)
  • Depending on customer settings for alerts and Safety Alert Seat availability, there will be a chime or haptic alerts associated with warnings
2021 GMC Sierra 3500HD Denali safety

AVAILABLE BED VIEW WITH ZOOM AND HITCH GUIDANCE

Bed View uses a camera in the Center High-Mounted Stop Lamp to allow you to see inside the bed to check on cargo while driving. When enabled, additional features such as a Cargo Bed Zoom View and Bed Hitch Guidance are helpful for hooking up a gooseneck/fifth-wheel trailer.

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