The 2025 GMC Sierra HD is available in a variety of trims, each designed to suit different preferences and requirements. The Pro trim provides a durable foundation with 17-inch steel wheels, a black grille, and LED reflector headlamps, making it a practical choice for hard work. The SLE trim adds a touch of refinement with 17-inch aluminum wheels, a chrome grille, and an EZ Lift tailgate for convenience. The SLT trim elevates the look with 18-inch aluminum wheels, chrome accents, and power-folding mirrors for added functionality. For off-road enthusiasts, the AT4 trim is equipped with 20-inch aluminum wheels, an off-road suspension package, and skid plates, ensuring it can tackle rugged terrains with ease. The AT4X, exclusive to the 2500 HD, takes off-road capability even further with a factory-installed 1.5-inch suspension lift and larger skid plates for added durability. For those seeking ultimate luxury, the Denali trim features 20-inch machined aluminum wheels, a Denali-specific grille, and GMC’s iconic C-shaped LED lighting, creating a commanding presence on the road. At the top of the lineup, the Denali Ultimate trim adds a power sunroof and power-retractable assist steps with LED perimeter lighting, offering the pinnacle of style and capability.

The 2025 GMC Sierra HD offers two robust engine options to meet a variety of performance needs. The standard 6.6-liter V-8 gas engine delivers 401 horsepower and 464 pound-feet of torque, making it a reliable choice for most tasks. For those requiring maximum power, the available Duramax 6.6-liter Turbo-Diesel V-8 engine provides 470 horsepower and an impressive 975 pound-feet of torque. This powerhouse is designed for heavy-duty towing and hauling, ensuring the Sierra HD is ready for the toughest challenges.

The 2025 GMC Sierra HD delivers remarkable performance, especially when equipped with the Duramax diesel engine. The 3500 HD offers a best-in-class maximum towing capacity of up to 36,000 pounds, while the 3500 HD gas engine variant boasts a maximum payload capacity of up to 7,237 pounds. A 10-speed Allison automatic transmission ensures smooth and efficient power delivery across all trims. The available four-wheel drive system with an AutoTrac active transfer case, independent front suspension, and solid rear axle provides stability and control, whether you're towing on the highway or navigating challenging terrain. For enhanced maneuverability, the optional Digital Variable Steering Assist offers precise handling.

The interior of the 2025 GMC Sierra HD combines rugged capability with premium comfort and advanced technology. With seating for up to six passengers, the spacious cabin is designed for both work and leisure. The available 13.4-inch diagonal GMC Premium infotainment system provides seamless connectivity with wireless Apple CarPlay and Android Auto compatibility, keeping drivers and passengers connected. The available 12.3-inch diagonal driver information center and 15-inch diagonal multicolor head-up display ensure critical information is always within view.

Safety is a priority in the 2025 GMC Sierra HD, with a comprehensive suite of standard and available features. The GMC Pro Safety package includes forward collision alert, automatic emergency braking, front pedestrian braking, lane departure warning, and IntelliBeam auto high beams. For enhanced security, the available GMC Pro Safety Plus package adds lane change alert with side blind zone alert, rear cross-traffic alert, and rear park assist.