





The 2025 GMC Sierra 3500HD AT4 with the 6.6L Duramax Turbo-Diesel V8 and AT4 Premium Plus Package offers a compelling blend of heavy-duty performance, off-road capability, and premium features. Here's an overview:​
Engine: 6.6L Duramax Turbo-Diesel V8
Horsepower: 470 hp @ 2,800 rpm
Torque: 975 lb-ft @ 1,600 rpm
Transmission: Allison 10-speed automatic
Drivetrain: 4WD with off-road suspension and twin-tube Rancho shocks
Towing Capacity: Up to 20,000 lbs
Payload Capacity: Up to 4,127 lbs
Technology Package:
15" multicolor Head-Up Display
Digital rearview mirror
AT4 Preferred Package:
Power sunroof
Premium materials and additional features
Off-Road High Clearance Step: Enhanced accessibility for rugged terrains
Adaptive Cruise Control: Maintains set speed and distance from vehicles ahead
Seating: Heated and ventilated perforated front leather seating surfaces
Climate Control: Dual-zone automatic climate control
Infotainment:
13.4" diagonal center touchscreen
12.3" diagonal digital Driver Information Center
Wireless Apple CarPlay and Android Auto compatibility
Audio System: Available Bose Premium Series with Centerpoint surround sound​
GMC Pro Safety:
Forward Collision Alert
Following Distance Indicator
Front Pedestrian Braking
Lane Departure Warning
IntelliBeam auto high beams
Blind Spot Monitor
Rear Cross Traffic Alert
Up to 14 available camera views, including HD Surround Vision​
Wheels: 20" gloss-black aluminum wheels
Lighting: LED projector headlamps with animated sequences
Tailgate: MultiPro Tailgate with six convenient functions
Bed Protection: Spray-on bedliner with GMC logo
The 2025 GMC Sierra 3500HD AT4 with the AT4 Premium Plus Package is designed for those who require robust towing and payload capabilities without compromising on comfort and advanced technology. Its combination of off-road readiness and premium features makes it a versatile choice for both work and leisure.