Led by the first-ever GMC Sierra Heavy Duty Denali Ultimate, GMC noted the 2024 model-year takes the Sierra HD lineup to new heights with turbocharged pulling power and elevated technology — offering the most trailering assistance technology in its class, according to the automaker.

In addition to the debut of the Denali Ultimate trim, the 2024 Sierra HD will build upon GMC’s premium off-road offerings, introducing the off-road optimized Sierra HD AT4X trim later in the model year.

“The new and enhanced 2024 Sierra HD builds on an already winning foundation,” said Duncan Aldred, vice president of Global Buick and GMC. “This truck elevates the HD segment with the introductions of the Denali Ultimate trim and will soon add the seriously off-road capable AT4X trim, further strengthening the dominance of the GMC truck portfolio.”

Tweet this! GMC adds new trim to 2024 Sierra HD lineup - check it out!

Updating a Workhorse

Check out these GMC Sierra Heavy Duty Highlights:

  • Enhanced power with the combination of the available 6.6L Duramax Turbo-Diesel V-8 and 10-speed Allison transmission delivering 470 horsepower and 975 lb.-ft. of torque and providing 25% more low-end torque vs. the current model for a greater feeling of power on demand
  • Max towing across the lineup, including:
    • Up to 21,9002 pounds on 2500HD Crew Cab
    • Up to 22,5003 pounds on 2500HD – a 4,000-pound increase over the current model
    • Up to 36,0004 pounds on 3500HD
  • Most available trailering assistance technologies in its class through GMC’s ProGrade trailering system, offering up to 14 camera views
  • Updated technologies including an available new, 13.4-inch-diagonal tablet-style infotainment touchscreen

The 2024 Sierra HD lineup includes 2500HD and 3500HD models, in Regular Cab, Extended Cab and Crew Cab configurations — with dual-rear-wheel models available on 3500HD. They support the lineup’s highest trailering capacity: up to 36,000 pounds. Available trims include Pro, SLE, SLT, AT4, Denali and Denali Ultimate, with the AT4X trim coming later in the model year.

The GMC Sierra 3500 HD Denali features numerous updates and upgrades for the 2024-MY.  -  Photo: GMC

The GMC Sierra 3500 HD Denali features numerous updates and upgrades for the 2024-MY.

Photo: GMC

2024-MY GMC Sierra HD Exterior & Interior Updates

The 2024 Sierra HD lineup is elevated with styling and design updates, inside and out. Exterior highlights include:

  • Revised front bumper, fascia, grille designs and finishes on each trim
  • Animated lighting when approaching, starting, or when using the turn signals
  • New wheel designs on SLE, AT4, Denali and larger 18-inch polished aluminum wheels on dual rear-wheel models
  • New 22-inch accessory wheels
  • Six new exterior colors (extra cost): Titanium Rush Metallic, Sterling Metallic, Volcanic Red Tintcoat, Redwood Metallic, Meteorite Metallic and Downpour Metallic
  • Rear wheelhouse liners standard on Denali and Denali Ultimate dual rear-wheel models

Inside, GMC added new interiors on SLE, and SLT trims, as well as GMC premium interior designs for AT4, Denali, and Denali Ultimate trims. There are also new color and stitching designs throughout, with more premium materials throughout the cabin.

Check out this interior view of the GMC Sierra 3500 HD Denali!   -  Photo: GMC

Check out this interior view of the GMC Sierra 3500 HD Denali! 

Photo: GMC

GMC Enhances the 6.6L Duramax Turbo-Diesel

The available enhanced 6.6L Duramax Turbo-Diesel, paired with the 10-speed Allison transmission, now delivers 470 hp (at 2800 rpm) and 975 lb.-ft. (at 1600 rpm) of torque. Specifically, GMC noted that low-end torque production increases up to 25% compared to the current model for improved towing performance.

Q: When did GMC come out with the multi-function tailgalte? 

A: GMC's MultiPro tailgate was first unveiled on the 2019 GMC Sierra Denali pickup in Detroit. We tested it out on a 2020 model soon after!  

The 2024 Sierra HD will also offer 2500 Crew Cab towing of up to 21,9002 pounds and max 2500 towing of up to 22,5003 pounds, enabled by a new available Max Tow Package.

According to GMC, additional changes and upgrades were designed to produce a more efficient combustion and enhance overall performance. This latest iteration of the Duramax engines adds additional refinements including:

  • An all-new, turbocharger with improved efficiency to boost low-end torque.
  • Increased power and torque over the entire operating speed range.
  • Improved engine braking with a more powerful turbo vane actuator and uprated valve springs.
  • New cylinder heads with improved cooling jackets.
  • An all-new combustion system within the heads that’s matched with next-generation, higher-flow injectors and greater fuel injection pressure.
  • All-new engine controller.

What is the All-New Sierra HD Denali Ultimate?

The first-ever Sierra HD Denali Ultimate is equipped with unique enhancements to the overall design and premium interior appointments, more standard technologies and standard turbocharged performance with the enhanced 6.6L Duramax Turbo-Diesel and Allison 10-speed transmission.

The Denali Ultimate is distinguished by an exterior featuring a unique grille and GMC badging in exclusive Vader chrome, along with exclusive 20-inch Ultra-bright machined aluminum wheels, and more. Additionally, Denali Ultimate will include a six-way MultiPro Tailgate with a standard Kicker audio system. Power assist steps also come standard.

The GMC Sierra 2500 HD Denali Ultimate is the newest addition to the Sierra pickup truck lineup.   -  Photo: GMC

The GMC Sierra 2500 HD Denali Ultimate is the newest addition to the Sierra pickup truck lineup. 

Photo: GMC

    Improving Gas-Engine Trailering Capability with 10-speed Allison Transmission

    The Allison 10-speed automatic transmission is now paired with the Sierra HD’s standard 6.6L gas engine. It replaces the previous 6-speed automatic, offering smaller “steps” between the gears, which GMC noted enables the 6.6L gas engine to hold closer to its peak power (401 horsepower and 464 lb-ft of torque) for longer periods.

    According to GMC, that translates into a more confident feeling of on-demand power, regardless of whether the truck is towing a trailer — but when it is, trailering performance and capability are enhanced thanks in part to the 10-speed configuration, along with the capability of channeling every single pound-foot of torque to the tires in every gear. 

    Enhanced Overall Trailing Assistance Tech

    The 2024 Sierra HD will also offer the most trailering assistance technologies in the heavy-duty class1 through the available ProGrade Trailering System. The ProGrade Trailering System includes a suite of available intelligent trailering assistance technologies designed to help streamline the hitching and towing process.

    Additionally, in total, the 2024 Sierra Heavy Duty offers up to 14 available camera views, including: 

    • Hitch Guidance with Hitch View: Provides a close-up view of the receiver hitch to help with alignment when connecting to a trailer. 
    • Bed View with Zoom and Bed Hitch Guidance: Allows you to see the cargo bed to help with fifth-wheel or gooseneck hitching or to briefly check on cargo.
    • Rear Side View with Trailer Length Indicator: With a compatible trailer attached and a turn signal activated, this view will show a full screen down the side of the truck along with a Trailer Length Indicator to aid in lane-change maneuvers by visually showing obstructions with the trailer in adjacent lanes.

    When Can You Get the New 2024 GMC Sierra HD?

    The refreshed 2024 GMC Sierra HD arrives at dealerships in the first quarter of 2023, with the AT4X coming later in 2023. Pricing will be announced closer to the start of production.

    For more information on new truck launches, updates, and GMC news, and to manage your newsletter subscriptions, be sure to sign up for Bobit Connect today! 

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