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GM's fullsize SUVs boost highway mileage by nearly 10 percent

We met the redesigned 2015 versions of the Chevrolet Suburban and Tahoe, and the GMC Yukon and Yukon XL at the 2013 LA Auto Show. Improved gas mileage numbers have been announced to go along with the improved exteriors and interiors, with city mileage improving by seven percent and highway mileage going up by nearly ten percent; you'll now get 16 miles per gallon in the city and 23 on the highway.
The only applies to models with the 5.3-liter engine, though, not the premium Yukon Denali and Yukon XL Denali SUVs with the 6.2-liter motor. Still, the 5.3 gets you more power than previously, with 355 horsepower and 383 pound-feet of torque underfoot, on top of the improved fuel economy numbers. The 6.2-liter sticks with official mpg ratings of 15 highway, 21 city. There's a brief press release below with words straight from the horse's mouth.

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 renders new Chevy Colorado, GMC Canyon pickups

At a series of industry seminars in Traverse City, MI today, General Motors executive vice president Dan Ammann gifted us with our first glimpse of the upcoming midsize pickup range from Chevrolet and GMC.
Just two slivers of nose are all we can see of the soon-to-be announced Chevy Colorado and GMC Canyon, though the teaser image does make plain that the pair will follow the styling cues (at least up front) found on big brothers Silverado and Sierra.
GM hasn't given us much in the way of detail in its ultra-brief press release that accompanied the teaser image, which is to be expected. We're told only that the pair of trucks are designed to be "capable, versatile and fuel-efficient alternatives to full-size pickups" and that production will start sometime in 2014, at the Wentzville, MO assembly center.