The Adaptive Cruise Control (ACC) feature (RPO code KSG) will be offered on the refreshed 2024 GMC Sierra HD, adding a key GM active safety technology to the heavy duty truck. The addition of ACC will mark the very first time that this advanced technology has been offered on the Sierra HD.
As a reminder, Adaptive Cruise Control uses GM Forward Collision Alert sensors such as radar and cameras to scan the road ahead. Once activated, ACC will automatically accelerate and brake the vehicle up to moderate levels to maintain a following gap (distance), as chosen by the driver, between the GMC Sierra HD and the vehicle ahead. This reduces the need for the driver to frequently brake and accelerate when following in traffic. The system was updated for the Sierra HD to account for increased drag and longer braking distances when towing a trailer, which is also the case for the Sierra HD’s corporate stablemate, the 2024 Chevy Silverado HD.
Adaptive Cruise Control will be available on all GMC Sierra HD trims for the 2024 model year, as follows (RPO codes in parentheses):
- Pro: standalone option
- SLE: included and only available with the Preferred Package (PDQ)
- SLT: included and only available with the SLT Preferred Package (PDY)
- AT4: included and only available with the AT4 Preferred Package (PDO)
- Denali: included and only available with the Technology Package (CWM)
- Denali Ultimate: standard
We also expect that ACC will be available on the upcoming Sierra AT4X HD, though GMC has yet to confirm this.
Beyond Adaptive Cruise Control, the 2024 GMC Sierra HD is getting an overall refresh that features an updated front fascia, including revisions to the front bumper and grille. Six new exterior colors and several new wheel designs join the lineup.
The big news, however, lies inside the truck, as most models get an overhauled cockpit. The SLE and SLT trim levels get a unique interior treatment, while the AT4, Denali, and Denali Ultimate trims receive a premium interior design. Despite the refresh, the shifter stays on the steering column rather than moving to the console, as HD customers prefer the extra console space enabled by a column shifter.
As for the powertrain, most 2024 GMC Sierra HD trucks feature the naturally aspirated 6.6L V8 L8T gasoline engine as standard. The atmospheric eight cranks out the same 401 horsepower and 464 pound-feet of torque as it did prior to the 2024 model year refresh. However, the 6.6L V8 L5P turbodiesel Duramax engine, optional on most trims but standard on the Denali Ultimate, now generates 470 horsepower and 975 pound-feet of torque, up from 445 horsepower and 910 pound-feet. No matter the engine, all 2024 Sierra HDs feature the Allison-branded ten-speed automatic transmission, replacing the six-speed previously used in conjunction with the L8T.
The refresh also brings two new trim levels – the range-topping Sierra HD Denali Ultimate and the soon-to-be-announced Sierra HD AT4X. Finally, the trucks also get the new GCW Alert system, which monitors gross combination weight while trailering as well as Automatic Emergency Braking across the whole lineup as a standard feature.