2007 Gmc Sierra 1500 Sle 4x4 - 5.3l Vortec V8 - Z71 Pk - Fully Loaded - Nice 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.

2014 GMC Sierra [w/video]

Big And Boxy Might Be Best
As immense fans of the Back to the Future trilogy, we sometimes like to envision an alternate timeline in which General Motors had killed off GMC and kept Pontiac instead. The G8 GXP would still be on the road handily beating German sport sedans costing twice as much, while the lowly G3 would morph into a true subcompact-killer based on what is now the Chevrolet Sonic RS. While we're at it, let's go ahead and imagine the G6 has become the best-selling car in the US and the Torrent crossover is selling 20,000+ units per month. Far-fetched, we know.
The thing is, these fanciful statements would have to be true to make the case against keeping GMC. Pontiac may have offered more excitement than GMC, but money talks, and a full line of trucks, crossovers and SUVs have made a lot more money for GM than the arrowhead brand ever did. How much? As we learned last month, about two-thirds of GM's global profits came from its fullsize trucks, and GMC's trucks typically have thicker margins than their Chevrolet counterparts.

Driving a 1964 Volkswagen Beetle, and the 2021 Kia K5 arrives | Autoblog Podcast #634

In this week's Autoblog Podcast, Editor-in-Chief Greg Migliore is joined by Road Test Editor Zac Palmer and News Editor Joel Stocksdale. They start with what they've been driving this week, including the 2020 GMC Sierra 1500 diesel, 2020 Volkswagen Atlas Cross Sport and a 1964 Volkswagen Beetle. They move on to the news, covering the 2021 Kia K5, Geneva Motor Show (canceled again), Maserati's new engine and a new extended reality experience here at Autoblog. Finally, the guys spend some money for a listener who just had twins. Autoblog Podcast #634 Get The Podcast iTunes – Subscribe to the Autoblog Podcast in iTunes RSS – Add the Autoblog Podcast feed to your RSS aggregator MP3 – Download the MP3 directly Rundown Cars we're driving 2020 GMC Sierra 1500 AT4 diesel 2020 Volkswagen Atlas Cross Sport 1964 Volkswagen Beetle 2021 Kia K5 Geneva Motor Show cancelled Maserati engine Extended Reality with the Mustang Mach-E Spend your money Feedback Email – Podcast@Autoblog.com Review the show on iTunes Related Video: