The 2025 GMC Sierra 2500HD AT4 Diesel available at Stockton Auto Mall is a heavy-duty truck built for serious capability, off-road performance, and premium comfort. Designed for drivers who need both strength and refinement, the AT4 trim combines rugged styling with advanced technology and everyday usability. Under the hood, it’s equipped with the legendary 6.6L Duramax turbo-diesel V8 engine, paired with a smooth 10-speed Allison automatic transmission, delivering exceptional torque and dependable performance for towing and hauling.

Engineered for adventure, the Sierra AT4 comes standard with a factory off-road suspension featuring Rancho shocks, skid plates, and hill descent control, giving you confidence on rough terrain and job sites alike. With a maximum towing capacity of up to 21,300 pounds when properly equipped, this truck is more than capable of handling trailers, heavy equipment, or recreational gear.

Inside, the cabin offers a refined and functional design with leather-appointed seating, heated and ventilated front seats, and a large 13.4-inch touchscreen infotainment system with wireless Apple CarPlay and Android Auto integration. The spacious interior comfortably seats up to five passengers while maintaining a durable, work-ready feel.

This particular truck comes with a clean title and a clean CARFAX report, giving you peace of mind and confidence in its history. If you’re looking for a diesel truck that delivers powerful performance, off-road capability, and modern comfort, this 2025 GMC Sierra 2500HD AT4 is ready to get the job done.