The New Duramax 6.6L V8

The latest Duramax 6.6L V8 engine from GMC is nearly all-new, sharing little more than the bore and stroke from the previous version. With the redesign comes more horsepower and almost 20% more torque. Despite power going up, noise has gone down substantially; at idle, the new 2017 Duramax produces 38% less noise. All of these improvements are the result of a number of intelligent and innovative design choices by GMC engineers with the aim of making the new Duramax engine the perfect motor for the 2017 Sierra HD.

Because the Sierra HD needs to excel as both a work truck and a refined long-haul companion, the new Duramax V8 was made quieter and more powerful than ever. The fuel system, oil pan, rocker covers, and many other components were redesigned to dampen noise, making this the quietest Duramax to ever be fit to a truck. None of that has come in the way of exceptional power and power delivery, however: the new Duramax churns out 445 horsepower and an astounding 910 pound-feet of torque. That torque comes early, too, with 90% of peak torque available at just 1,550 RPM, sustaining up to 2,850 RPM. This means that you and your load start to accelerate the moment you put your foot down and don’t stop until you’re cruising down the highway.

The 2017 6.6L Duramax is tightly integrated with the Sierra HD, particularly the all-new induction system. Cool air comes in through the signature hood scoop and is run through the variable-geometry turbocharger which produces up to 28PSI of boost, while the bold front grill accommodates the enlarged capacity radiator and cooling system. Great energy was also expended making the Duramax an efficient and environmentally-friendly engine. The advanced solenoid injectors can deliver up to seven burst of fuel per combustion event, ensuring the fuel burns as completely as possible. This increases engine output and reduces emissions. The exhaust recirculation system lowers combustion temperature to cut down on NOx emissions and the engine can run on B20 biodiesel blend. Working together, all of these systems produce a powerful, quiet, and efficient engine.

By redesigning nearly the entire engine, GMC engineers have created an ideal power plant for your ideal truck. The improvements on the already-great Duramax aren’t just esoteric, either; you’ll hear and feel them as soon as you turn the key. Whether you’re hauling a horse trailer or touring a jobsite, Duramax give you the diesel power you need.