General Motors has announced power figures for their newest Duramax diesels that will be showing up in the 2017 Chevrolet Silverado HD and GMC Sierra HD. The big deal is the redesigned engine's 445 hp and the rather nice looking 1,234 Nm (910 lb-ft) of torque.
That's 19-percent more torque than before for the 6.6L turbo-diesel V8, but GM is quick to point out that they've also reduced idle noise by 38-percent. While some may not be happy to have their diesels quieted down, most owners will probably appreciate the increased refinement.
The new engine shares only the bore and stroke dimensions from the old one, and also has an all-new control system. The block is all-new as are the heads. The whole thing has been strengthened, as has the rotating assembly. There is better oil and coolant flow to keep things running well. There is also a new EGR system with cooler.
The new air intake uses a big, bold hood scoop to pull cool dry air to both feed the engine and to keep under the hood cool. That helps it maintain the power level under extended high load and high-temperature conditions.
The new turbo has variable vanes and electronic control, and has a higher max boost pressure than before. Now up to 28 psi. There are also changes to improve the exhaust-brake system. A new glow plug system allows the engine to start from cold in less than three seconds, at temperatures as low as -29 C.
The new engine will be matched to the previous, but highly regarded, Allison six-speed automatic.
All of that power is great for towing and hauling, but a big trailer isn't really a good way to show off what you can do. So for that, GM has gone for a Guinness record. They hooked up a massive 12.1 m by 24.3 m American flag behind a Duramax Silverado and pulled it 100 m around Texas Motor Speedway to set a record for largest flag ever pulled by a moving vehicle. A team of workers ensured that the flag didn't touch the ground when starting and finishing the attempt.