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 opens military discount to 21M veterans and their spouses

May marks the start of National Military Appreciation Month, and General Motors is getting into the spirit by expanding its military discount program to, well, just about everyone. That includes a total of 21 million military veterans and their spouses, along with the current slate of active duty, reserve, and National Guard members. The discount can slash thousands of dollars off the price of a new Buick, Chevrolet, or GMC vehicles, with Automotive News listing an $1,100 discount on the top gas-powered version of the Malibu, the Premiere. Those that want a bit more spice can get $1,700 off the price of a last-generation 2015 Camaro SS, while truck buyers will enjoy $3,000 off the Chevy Silverado All Star. That's just a start, though, since the military discount can be paired with other GM incentives. The discount doesn't apply to everything, though. Some are understandable – none of Cadillac's vehicles are included in the deal, nor is the Corvette Z06. You'll also be unable to apply the discount to a range of base-level trims, like the Chevy Cruze or Equinox L, the base Colorado, or the entry level GMC Acadia, Canyon, and Terrain. A full list is available at GM's dedicated military discount website. GM's expanded discount plan runs from today through May 31. News Source: General MotorsImage Credit: General Motors Buick Chevrolet GM GMC Car Buying Car Dealers Military

5 things we love about the 2019 GMC Sierra AT4

NEW YORK — The 2019 GMC Sierra AT4 proves that GM's upmarket truck and SUV brand is getting serious about offering rough-and-tumble capability to rival the Ford F-150, Toyota Tundra, Ram 1500 and Nissan Titan. Until the Sierra AT4 rolled onstage at a media event in lower Manhattan, prior to this year's New York Auto Show, the GMC brand had been more focused on luxury touches like fancy chrome wheels and posh interiors — no surprise, considering the upscale SLT and Denali trim levels account for the vast majority of GMC sales. So now GMC wants to get muddy and adventurous? Well, yes and no. The AT4 adds hardware that'll take truck buyers off the beaten path, though this GMC isn't anywhere close to being a Spartan, no-frills work truck. To better explain, let's look at five key features we love about the 2019 GMC Sierra AT4: More than stickers and chrome The Sierra AT4 isn't a cynical marketing ploy, there is some true all-terrain toughness built into this pickup truck. A factory-installed lift kit raises the AT4 by two inches, while Rancho monotube shocks, a locking rear differential, a two-speed transfer case and standard all-wheel drive prove this GMC can dare to venture off paved surfaces — though you might risk getting mud and muck on the truck's handsome 18- or 20-inch alloy wheels. Power and economy The Sierra AT4 comes standard with a 5.3-liter V8 coupled to an eight-speed automatic transmission. In the standard Sierra 1500, this engine produces 355 horsepower. GMC didn't mention engine specs here in New York, though it's possible the AT4 might get a small power bump. This engine should be plenty for most truck buyers, though GMC offers two tempting alternatives. These include a turbo-diesel 3.0-liter inline-six, along with a 6.2-liter V8. Both motors are paired to stop-start fuel-saving systems, along with a new 10-speed automatic transmission. Carbon fiber cool factor The GMC Sierra's available carbon-fiber cargo bed, called CarbonPro in GMC-speak, trims 62 pounds of weight, as compared to a traditional all-steel bed. This slick feature uses carbon composites for interior panels and, judging from GMC's videos of burly bricks and huge hammers being thrown into a CarbonPro cargo bed, it should prove more than up to the task of ... well, having someone throw bricks and hammers into the cargo area.