2025 GMC Sierra 3500 HD

The new Sierra 3500 HD for 2025 offers six trims: the Pro, SLE, SLT, AT4, AT4X, Denali, and Denali Ultimate. The Pro features LED projector headlights and 18-inch steel wheels, while the SLE showcases 18-inch alloy wheels and a multifunction tailgate with power locks and lift assist. Six of the nine color options — Cardinal Red, Downpour Metallic, Onyx Black, Sterling Metallic, Summit White, Thunderstorm Gray, Titanium Rush Metallic, Volcanic Red Tintcoat, and White Frost Tricoat — are available per trim.

The SLT features LED taillights, cargo box lights, and dark gray 18-inch wheels. The AT4 models feature high-gloss black mirror caps and body-color bumpers. While the Denali has a bright chrome grille, mirror caps, and 20-inch machined wheels, the Denali Ultimate has dark chrome trim, power assist, and LED lighting. LED projector headlamps are standard, while the MultiPro Tailgate is available only on higher trims.

The standard 6.6-liter V-8 gas engine delivers 401 horsepower at 5,200 rpm and 464 pound-feet of torque. The 6.6-liter Duramax turbo-diesel V-8 engine produces 470 horsepower and 975 pound-feet of torque for heavy towing at just 1,600 rpm. Its substantial torque makes it easy to pull trailers uphill or haul heavy loads.

While the Duramax comes standard on the Denali Ultimate, it is optional on other trims. Both engines integrate a 10-speed Allison automatic transmission.

With the optional diesel engine and dual rear wheels, the Sierra 3500 HD tows up to 36,000 pounds. It handles payloads reaching 8,920 pounds, while the 3500HD Chassis Cab achieves a maximum gross combined weight rating of 40,000.

Despite its size, the AT4X AEV with the diesel engine accelerates from 0 to 60 mph in 6.6 seconds. The ProGrade Trailering System simplifies towing with 14 camera views. Combined with powerful braking and a tight turning radius, this truck exceeds expectations.

The SLE and higher trims feature a 13.4-inch touchscreen with Google and a 12.3-inch digital cluster. Crew cabs offer ample space with 43.4 inches of rear legroom. Higher trims offer 16-way power front seats with massage functions.

The Denali Ultimate includes a 12-speaker Bose premium sound system, and an optional 15-inch head-up display projects important information onto the windshield. The cabin, which features practical storage, blends durability with comfort.

GMC loads every Sierra 3500 HD with safety technology, such as automatic emergency braking, forward-distance alerts, and an HD camera for backing up. The lane departure warning alerts you if you drift out of your lane.

The SLE or higher trims feature a surround-view camera system with up to 15 angles, including a transparent trailer view. You can also add adaptive cruise control, which adjusts your speed to maintain a safe traveling distance. These systems work together to keep you and your cargo secure.