2015 Chevrolet Tahoe Ls on 2040-cars

Auto blog

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.

GM cutting Chevy Sonic, Buick Verano production [UPDATE]

UPDATE: A previous version of this story indicated that Orion Assembly would be idled for seven weeks, from February 16 through April 6. This was incorrect. The factory will instead only be idled for the weeks of February 16 and April 6. The story has been edited to reflect this. General Motors has announced that the factory responsible for the Buick Verano and Chevrolet Sonic will be idled for the weeks of February 16 and April 6, with blame being placed on excess supply. The Orion Assembly plant, about 45 minutes north of GM's Renaissance Center headquarters, employs about 1,800 people, but they'll be given a pair of furloughs as inventories of the sub-compact Sonic and premium compact Verano reach 127 days and 84 days, respectively. That works out to 26,600 Chevys and 9,800 Buicks waiting for buyers. According to Automotive News, the compact Chevy sales bested the industry average in 2014, jumping up nine percent versus the the overall segment's eight-percent gain, while the Buick sedan's sales were down four percent. When asked about the shutdown, a GM spokesman told AN that it will "build to market demand," while also pointing out that the company did not comment on production plans. News Source: Automotive News - sub. req.Image Credit: Bill Pugliano / Getty Images Plants/Manufacturing Buick Chevrolet GM buick encore orion assembly

Next-gen GMC Sierra spied with diesel power

The next generation of GM trucks is arriving soon, and we're expecting a huge leap forward over the current lineup. The Chevy Silverado and the GMC SIerra sell extremely well, but haven't done much to move the segment forward in a long time. The Ford F-150 has an all-aluminum body and turbocharged V6 power. The Ram 1500 gained a diesel and coil spring suspension. These spy shots show that diesel may be in the cards for GM. Some quick shots and copious use of flash show what is most likely a tank for diesel exhaust fluid and a diesel particulate filter, both necessary equipment for any modern diesel. It's unclear what form factor that engine will come in, though GM has a number of engines to choose from, including the 2.8-liter inline four that's found in the Colorado and Canyon, though that may be a little light duty for the Silverado and Sierra. Other rumors surrounding the trucks suggest a move to an aluminum cab while retaining a steel bed. That seems like a reasonable move for GM, even if the company was attempting to shame Ford for its move to aluminum a few years ago. Look for more news as early as the Detroit Auto Show in January. Related Video: Featured Gallery 2019 GMC Sierra spy shots View 21 Photos Image Credit: Spied Bilde Spy Photos Chevrolet GMC Truck