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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.

Nissan Leaf has 2nd-best sales month ever, Chevy Volt does a 2013 repeat [UPDATE]

UPDATE: The official press release says that "Volt [sales were] up 7 percent," but Randy Fox let AutoblogGreen know that this is simply due to a change in the fleet/retail mix between March 2013 and 2014. The actual number sold was exactly the same in the two months. A month ago, Nissan's director of EV sales and marketing, Toby Perry, said he expected to see the Leaf's sales momentum continue into March. It wasn't a big leap, since January and February were slow sales months in 2013 (around 640 each) before a big climb to 2,200 in March. In 2014, the first two months of the year were better (around 1,300 each) but Nissan can still be happy that the Leaf just had the best March ever and its second-highest sales month ever, with 2,507 sold. That's a 12.1 percent increase from 2013 and Perry said in a statement to AutoblogGreen that one reason is all of the buyers who are becoming evangelists for the vehicle. "We've also seen an increase in showroom traffic as we enhanced our marketing presence in March," he said. Nissan pointed to cities like Washington, DC, Raleigh-Durham, NC and urban areas in Texas as strong Leaf markets last month. On the Chevy Volt front, January and February were also slow months in 2014, down roughly half from the 2,000-ish the plug-in hybrid was selling at the end of 2013. For 2014, sales were up slightly from the first two months of the year and Chevy spokesman Randy Fox told AutoblogGreen that the March number was "pretty flat, year-over-year." Even with that warning, we were surprised to see the total come in at 1,478. Why's that? Because the total for March 2013 was ... 1,478. So, yeah, that's pretty steady even if there were 26 selling days in March period this year compared to 27 last year. As always, our more complete report of last month's green car sales will be coming soon. News Source: General Motors, Nissan Green Chevrolet GM Nissan Electric Hybrid PHEV ev sales

Next Chevy Silverado could get this built-in tailgate step

General Motors just received patent approval for a tailgate step in a pickup bed. And given the timing, don't be surprised if you see this on the upcoming 2019 Silverado pickup (not the mention its GMC Sierra twin), expected to arrive in late 2018. According to the patent, granted in December of last year, the whole mechanism is housed in the tailgate assemble. The magic happens when a portion of the top half of the tailgate swings down and a step folds out. There's also a handle that locks into position to help climb up into the bed. As trucks get bigger and taller over the years, it gets harder and harder to access the cargo bed. Ford's solution with the 2009 F-150 was a step that slides out from the end of the tailgate. Back then, Chevy made an ill-advised ad highlighting the feature for Ford. And while Howie Long mocked the F-150's "man step" Ford saw almost a third of its trucks with the option in the first year. The GM design seems to improve on Ford's idea as it appears to be wider and has a back to the lower step. That is, you don't have to worry about stepping through the ladder-rung design as on the F-150. Ford's tailgate step later spread to the F Super Duty, and other cargo access assists have proliferated through the truck world. On the most recent redesign, the Chevrolet Silverado took a trick from the Avalanche and added cutouts to the corners of the rear bumper that act as a foothold. Ford also offers a deployable side step, Chevrolet has running boards that scoot rearward with a kick of the boot, and Ram offers fixed wheel-to-wheel side rails. Nissan is in on the game too, with an optional folding step that tucks under the rear bumper. We don't expect Chevrolet to comment on when or if we'll see this feature in the showrooms. But given that engineers are already hard at work on the next Silverado and the timing of this patent lines right up with the new truck's development cycle, we'll be disappointed if this patent stays in the file cabinet. Related Video: