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Chevy's 6.6-liter Duramax is pretty much all new

To say there's a heated battle in heavy-duty pickups is an understatement, with Chevrolet, Ford, and Ram constantly trading blows of increased torque, horsepower, and towing capacity. The latest salvo is the revised, more powerful turbo diesel 6.6-liter Duramax V8 in the 2017 Chevy Silverado. It has 910 pound-feet of torque, an increase of 145, putting it nearly level with the Ford Super Duty. Here's a closer look at where those gains come from. How exactly did Chevrolet add all that torque plus 48 horsepower? The automaker essentially took a fine-tooth comb to the entire engine. Chevy says it changed 90 percent of the V8, and the cumulative effect of those small changes adds up to big increases. As you might guess, the turbocharger is updated. The larger unit features electric actuation of the variable nozzle turbine (VNT), and what Chevy calls a double axle cartridge mechanism that separates the VNT moving parts from the housing. That helps with heat performance as well, with a claim that the exhaust side of the turbo can run continuously up to 1,436 degrees Fahrenheit. Helping that cause are six exhaust gaskets made of Inconel - an nickel alloy that contains chromium and iron – and upgraded stainless steel for the exhaust manifold. Despite having the same cast iron cylinder block, albeit with some minor enhancements, the engine has new cylinder heads, pistons, piston pins, connecting rods, and crankshaft, which have all been upgraded to handle 20 percent higher cylinder pressures. Alongside the increase in pressure, Chevrolet also increased the cylinder head's structure with a honeycomb design. The pattern features high-strength aluminum with dual layer water jackets that not only improve strength, but also optimize water flow for better cooling. For 2017, the cylinder head also benefits from integrated plenum that aids the engine in getting more air under heavy loads. The cylinder head isn't the only component to get a minor update, as the pistons have a larger diameter pin for improved oil flow. The same detailed improvements has been bestowed to the humble connecting rods (second in our hearts only to the inanimate carbon rod). The new design has the bolts oriented roughly 45-degrees to the rod instead of parallel. The angle split design, as it's called allows for easier passage through the cylinder.

Chevrolet Silverado, GMC Sierra could get independent rear suspension

The Chevrolet Silverado and the GMC Sierra could reportedly receive a variant of the four-link independent rear suspension found under the new Tahoe and Suburban. While that's not a surprise, a recent report suggests electrification, not comfort, convinced General Motors to make the change. Replacing the time-tested solid rear axle with an independent suspension will improve comfort, handling and off-road prowess, while adding weight, and likely making the trucks a little bit more expensive. It's a fair trade-off, but GM Authority learned the real reason for the swap is that at least one of the pickups will spawn an electric model, and it's more difficult to package a bulky battery pack around a solid rear axle. The independent rear suspension takes up far less space, even if it has more moving parts. General Motors will build its first regular-production electric pickup on an evolution of the Silverado's T1 platform named BT1, according to the same source. The b stands for -- you guessed it -- batteries. The firm reportedly doesn't want to make two suspensions for cost reasons, so the independent setup will come standard regardless of whether the truck runs on gasoline, diesel, or electricity. As a bonus, Chevrolet and GMC could choose to offer their T1-based trucks with Magnetic Ride Control or an air suspension, options available on the 2021 Suburban and Tahoe. The independent rear suspension will also find its way to the next-generation GMC Yukon due to be revealed January 14, and to the 2021 Cadillac Escalade scheduled to make its debut February 4. The long-rumored, born-again Hummer will get it, too, because it will arrive as an electric model built on the BT1 platform. It's worth noting none of this is official, and General Motors has remained quiet about what's next for its new suspension design, and what will be under its electric truck's sheet metal. If the GM Authority report is accurate, the Silverado (pictured) and the Sierra could ditch their solid rear axle for the 2021 model year. The change will likely be accompanied by other tweaks inside and out. Featured Gallery 2019 Chevrolet Silverado 1500 View 16 Photos Chevrolet GMC Truck

How GM engineers are using diaper 'snow' to keep you warm

Testing how snow affects General Motors' vehicles isn't really a problem right now for the company's engineers, but in the dog days of summer the process isn't exactly easy. The only real option is for them to book time at the automaker's climatic wind tunnel. However, a flash of brilliance from an engineer allows snow to be simulated regardless of the temperature outside, and the discovery is all because of his daughter's wet diaper. The realization came to GM Thermal Systems engineer Nicholas Jahn while he was swimming with his daughter and noticed how her diaper ballooned in size in the water. He found out the substance that makes this possible is called sodium polyacrylate. When the material gets wet it grows and forms fluffy flakes that are a close imitation of snow. Best of all, the stuff can be prepared easily any time of the year, and it's reusable. The engineering team uses the material to test the effectiveness of the heating systems of GM's vehicles. They spread the sodium polyacrylate over the inlets at the base of the windshield to obstruct the airflow and then crank the heater. After some time, they can see how much is being sucked into the system and design more efficient systems in the future. See how the process works in the video above and read about the diaper discovery in GM's press release below. Diapers Change Chevy Cruze Winter Warm-up Time GM validation engineer uses diaper material "snow" to reduce frigid drives 2015-01-06 DETROIT – An item commonly found on an infant's changing table is helping General Motors' engineers simulate snow year round, ensuring heating systems in cars like the 2015 Chevrolet Cruze can quickly and efficiently warm its interior. Packed snow can prevent air from entering the inlet panel at the bottom of the windshield, obstructing the flow of air into the heating system and reducing the amount of air it can push out. This can lead to less efficient warming of the car's interior and windshield defrosting. "The last thing anyone wants to do when it's freezing cold out is scrape their windshield," said Nicholas Jahn, GM Vehicle Thermal Systems engineer. "The testing we perform on the Chevrolet Cruze with the diaper material allows us to maximize the car's heating capabilities." Ironically, Jahn stumbled upon his diaper-based testing method in the middle of summer. During a swim with his daughter, he noticed her diaper multiplied in size when it came into contact with water.