2014 Chevrolet Silverado 1500 High Country on 2040-cars

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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.

A conversation with GM's Mark Reuss on MPG, aluminum and Corvettes

There was plenty to talk about when General Motors hosted its annual mid-December holiday media reception a few months ago. GM had just decided to pull its global Chevrolet brand out of major European markets, where Chevys have competed directly with GM Europe Opel and Vauxhall vehicles, and the US government had sold its last remaining shares of GM stock. But most important was the company's just-reshuffled leadership. Post-bankruptcy CEO Dan Akerson had announced that he would step aside and that 52-year-old Mary Barra would replace him on January 15. Not only would she be the first woman to lead a major automaker, she would also be GM's first engineer CEO since Bob Stempel in the early 1990s. "I look at 2013 and 2014, as the retooling of General Motors" - Mark Reuss Replacing her as executive VP for global product development (and purchasing and supply chain) would be 49-year-old Mark Reuss, who had served a stellar four years as North American president, and elevated to corporate president (from executive VP and CFO) would be 42-year-old Dan Amman. All three are relatively young auto enthusiasts who are liked and respected inside and outside the company, and their collective talents and experience are highly complementary. I've interviewed Barra and found her smart, personable and knowledgeable, though she carefully walks the corporate line in speaking and answering questions. I met and chatted with Ammann for the first time at that holiday reception, and he made a good first impression. But I've known Reuss for some time as a genuinely good guy and a highly capable and inspiring leader, and I believe he is exactly the right person for the global product responsibility once famously held by the outspoken, oft-controversial Bob Lutz. So I jumped at an opportunity to join a group interview of Reuss (with mostly business reporters) at the Detroit Auto Show in January. It was an interesting session of mostly good questions, which he answered with refreshing candor and humor. "I look at 2013 and 2014, as the retooling of General Motors," Reuss said. "We've taken down almost every plant in North America, converted and turned it this last year, and to do that with award-winning vehicles and pretty flawless launches is key. We have to keep the train rolling on great product, because the rest won't happen without the best product, period." A reporter asked whether GM was pushing big trucks, SUVs and Corvettes again because gas is cheap. "No," Reuss said.

GM natural gas-powered vans recalled due to possible leak

General Motors is recalling almost 3,200 of its compressed-natural-gas powered utility vans because of possible leaks. GM and the National Highway Traffic Safety Administration (NHTSA) released a notice last week saying that 3,196 Chevrolet Express and GMC Savana CNG vans are on recall, though no accidents have been reported due to the possible issue. The recall is specifically for vans for model years ranging from 2011 to 2014. The recall stems from a potential leak from the compressed natural gas high-pressure regulator, and such a leak could cause a fire or explosion. GM will replace the vehicles' high-pressure regulator in order to fix the problem, will do it free of charge and is instructing owners to contact Chevrolet or GMC customer service to arrange for the parts replacement. Utility vehicle makers like General Motors have pushed for fleet sales of CNG-powered vans and trucks for the past few years and have touted them for their cheaper refueling costs relative to standard gasoline, not to mention the fact that natural gas can be readily sourced from throughout North America (thanks, fracking). According to CNGPrices.com, compressed natural gas sells for about $2.22 a gallon, on average, while the AAA is pegging the average price of gas at $3.34 a gallon. NHTSA has posted information on the recall here. Featured Gallery News Source: NHTSA via Reuters Green Chevrolet GM GMC Natural Gas Vehicles CNG gmc savana