2014 Gmc Sierra 1500 Sle on 2040-cars

Auto blog

GM diesel pickups first to undergo extra EPA, CARB testing

The effects of Volkswagen's long-running diesel emissions evasion are starting to spill over to other automakers, but General Motors is taking things in stride. The 2.8-liter, four-cylinder Duramax in the 2016 Chevrolet Colorado and GMC Canyon is the first engine to get extra scrutiny by the Environmental Protection Agency and the California Air Resources Board, Automotive News reports. Rather than just the usual in-lab test, it's also being checked on the road. However, the extra evaluation shouldn't have any impact on when the trucks with his mill hit dealers later this fall. "We're in our final stages of the EPA certification, and our launch is on track," Chevy spokesperson Otie McKinley tells Autoblog. The four-cylinder diesel in the trucks makes 181 horsepower and 369 pound-feet of torque, and the automaker is touting low NOx production. In the announcement for the Colorado's specs, the company calls it "the cleanest diesel truck engine ever produced by General Motors." The tech includes exhaust gas recirculation to lower combustion temperatures and improve emissions. There's also a urea tank like on the bigger diesels for full-size trucks, and it gets refilled in time with oil changes. An indication on the instrument panel lets drivers know when that's needed, too. Even with the more demanding testing, the company doesn't seem too worried about the four-cylinder passing. "Part of our development process is on-road and off-road [laboratory] testing," Scott Yackley, Chevy Trucks assistant chief engineer, said to Automotive News. In the wake of the VW scandal, the EPA has pledged more rigorous testing. Before, on-road emissions evaluations were largely limited to heavy-duty vehicles, but the agency has decided to apply the checks more often to other models. There's also now greater cooperation with Canadian authorities.

GM confirms 2015 Silverado, Sierra to get 8-speed automatic

When viewed alongside the next Ford F-150 and the Ram 1500, there is one thing that seems to be missing from the Chevrolet Silverado and GMC Sierra. Where the F-150 will rely on turbocharging and aluminum architecture and the Ram sports an eight-speed automatic and an air suspension, the General Motors twins lack a big, calling-card feature. They're very good, very refined trucks, but one could argue that they're not terribly innovative.
And while it might not be as flashy a feature as air suspension or a lightweight skin, the Silverado and Sierra will get their own eight-speed automatic for 2015, a transmission that will be paired with the company's Ecotec3 6.2-liter V8. The new cogswapper will also find its way into the GMC Yukon Denali, but for now, there's no indication why the Cadillac Escalade, Suburban, Tahoe and standard Yukon are being left out.
According to GM, the new gearbox is about the same size and weight as the current Hydra-Matic 6L80 six-speed. By the time the new powertrain combination enters production late this year, the EPA will almost certainly have gotten around to certifying the vehicles' fuel efficiency. Until then, feel free to speculate. The current Silverado with the 6.2 and six-speed auto returns 14 miles per gallon in the city and 20 on the highway. How much do you think the eight-speed will improve those figures? Scroll down for the official press blast from General Motors, and then head into Comments.

Supercharged 2015 GMC Yukon Denali sounds evil, runs 0-60 in 4.5 seconds

Speeding along in a sports car is undoubtedly a ton of fun, but some owners need the ability to carry a lot of people and their stuff and don't want to sacrifice the ability to put the power down. The tuners over at Hennessey have that demographic covered with their growling, supercharged power kits for the GMC Yukon Denali. The upgrades come in three forms for the SUV's 6.2-liter V8: HPE550 with 557 horsepower, HPE600 with 605 hp and HPE650 with 665 hp. This video showcases the full-bore version, and this Denali can definitely hustle in a straight line. The power bump comes courtesy of a 2.9-liter supercharger, intercooler and high-flow cylinder heads to add over 200 horsepower compared to stock, and the final result is a bellowing SUV that rears up off he line to throw the driver back into the seat. The sprint to 60 miles per hour lasts just 4.5 seconds. Check out this hasty hauler in action in the video above.