2009 Gmc Yukon Denali 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.

Sunday Drive: Spying an automotive future of performance

I spy, with my little eye ... the future of the automotive world here in the United States. That pretty much sums up this week's Sunday Drive, in which we pull out the most popular stories on Autoblog of the previous week and try to draw some sort of conclusion as to what binds them all together. This week, it's spy shots, starting with one of the biggest and baddest muscle cars the world has ever seen: the Dodge Challenger Hellcat. The Hellish coupe gets a new hood for 2019 with dual scoops, but that's about the only meaningful change for the new model year. No matter. As long as it's packing 700-plus horsepower under those two hood scoops, all will be right with the world. Moving on, we take keep the performance angle but move it from the street to the dirt with a new version of the Chevy Colorado ZR2 that we think is probably called the Bison. We think it'll keep the high-tech suspension bits of the regular ZR2, but add expedition gear that may include a snorkel and a winch. Which, if true, is pretty dang cool. Keeping the truck theme is the 2019 GMC Sierra. There's nothing particularly noteworthy about the trim level in which the truck was spied, and that's what makes this specific example interesting. Base-model trucks almost never get much attention, but they sell in droves to workers who need an honest-to-goodness truck for work or play and don't care about bells, whistles, or massive chrome badges. And finally we have the 2018 Jeep Wrangler, which is on fire on the sales floor right now. But those are all V6-powered Wranglers flying off the showroom floor. Soon, a turbocharged four-cylinder engine option will become available, and now we know that it will return up to 23 miles per gallon in the city and 25 on the highway. That makes it the most fuel efficient Wrangler that Jeep has ever sold. As always, stay tuned to Autoblog this week for all the automotive news that's fit to publish. 2019 Dodge Challenger Hellcat with twin-scoop hood spied with no camouflage Chevy Colorado ZR2 Bison caught testing 2019 GMC Sierra 1500 spied in base trim level 2018 Jeep Wrangler four-cylinder fuel economy revealed Spy Photos Chevrolet Dodge GMC Jeep Truck Coupe SUV Off-Road Vehicles Performance dodge challenger srt hellcat sunday drive

2023 GMC Sierra AT4X could swipe a few parts from the AT4X AEV

GM recently expanded its collaboration with American Expedition Vehicles beyond the Bison herd with the 2023 GMC Sierra AT4X AEV. This Jimmy takes matters further than the standard AT4X by increasing ground clearance, approach and departure angle, and breakover angle, improvements made possible by new stamped steel bumpers and a set of 33-inch mud-terrain tires wrapping 18-inch AEV Salta wheels. GM Authority says the AT4X AEV won't be the only Sierra to get special parts, crediting sources for the news that the standard 2023 Sierra AT4X will get some of the equipment from the special trim. According to the report, at some point for the coming model year, the off-road-focused Sierra will bolt on the AEV's stamped steel front and rear bumpers, stamped steel front skid plate, and 33-inch Goodyear mud terrains. If this is true, it's an intriguing move; the equipment list is nearly everything found on the proper AEV model. Going by that list, the only bits left off would be four additional skid plates, wheels, gloss black door handles, gloss black tailgate accent, and AEV logos. Judging from the GMC retail website, the grille that debuted on the AT4X AEV will also be on the standard AT4X.  GMC hasn't announced pricing for the 2023 range yet. The pickup will be carryover, but we would expect various well-known issues to increase the $78,300 price of the regular AT4X over the 2022 model. GMA believes "it's reasonable to assume" that a standard 2023 Sierra AT4X with some AEV parts would go up even more, whenever it hits the market — and this is on top of the Sierra's $1,500 price increase from making OnStar standard equipment. And after that, of course, the proper AT4X AEV would be more again.