2008 Gmc Acadia Slt-1 on 2040-cars

Auto blog

GM 6.2L EcoTec V8 rated at 21 mpg by the EPA

General Motors is already laying claim to best-in-class power for its new 6.2-liter V8 that will be offered in the 2014 Chevy Silverado and GMC Sierra this fall, and now it has released fuel economy numbers for the big engine. Available as an option on the Silverado LTZ and High Country (shown above) models as well as the the Sierra SLT and Denali trims, the 6.2L EcoTec3 V8 will return 15 miles per gallon in the city and 21 mpg on the highway on rear-wheel-drive trucks; these numbers drop by one mpg each on four-wheel-drive models.
These estimates are in addition to the engine's 420 horsepower, 460 pound-feet of torque and max trailering capacity of 12,000 pounds, and considering all that power it's not terribly far away from the fuel economy of GM's equally new 4.3-liter V6 and its rating of 18 mpg city and 24 mpg highway. This announcement comes just days after a report indicated that GM is unable to keep up with the demand of the 5.3-liter V8 in the fullsize Chevy and GMC trucks due to supplier issues. GM's official press release for the 6.2-liter V8's fuel economy is posted below.

Diesel Power finds the ultimate modified oil-burner

For nine years, Diesel Power magazine has run the Diesel Power Challenge, this year's grindfest being "a week-long torture test that features seven events, nine trucks, 8,000 horsepower, and nearly 15,000 pound-feet of torque." The road to being crowned "the most powerful truck" starts with a dyno run, and then continues through the completion of a CDL-style obstacle course, an eighth-of-a-mile drag race while towing a 10,000-pound trailer, a quarter-mile drag race without a trailer, a fuel economy test in the mountains and finally a sled-pulling test through a 300-foot-long packed-mud pit.
What kind of trucks get into such a fight? Last year's winner, for instance - who upgraded his truck this year to prove he didn't "luck into the win" - drives a 2008 Ford F-250 Super Duty with a 6.4-liter Power Stroke V8 upgraded with a custom intake, Elite Diesel triple turbos and a two-stage nitrous system. Another competitor has a 2005 Dodge Ram 2500 powered by a 5.9-liter Cummins inline-six, upgraded with Garrett turbos, dual-stage nitrous, a seven-inch exhaust stack and twin fans built into the bed to cool the Sun Coast Omega transmission. The numbers on that truck: 1,255 horsepower, and 2,063 pound-feet of torque at the wheels. Naturally, as the image above might suggest, things don't always end well.
You'll find all five videos covering this years challenge below. A scene in the dyno video sums it all up perfectly: a competitor leaves his nitrous on too long and the crew is treated to some ominous poppings, he leans out the window, throws both hands up and shouts, "Amer'ca!"

GM readying aluminum-body fullsize pickups

Ford's extensive use of aluminum in its 2015 F-150 is a big deal. A really big deal. Big enough, in fact, that General Motors is reportedly changing its fullsize pickup strategy. According to The Wall Street Journal, The General has locked in partnerships with Alcoa Inc. and Novelis Inc. - companies that will supply aluminum for the next-generation Chevrolet Silverado and GMC Sierra trucks.
"Ford's introduction of the 2015 F-150 pickup truck was a game changer, and it's the first, not the last, conversion of this type," Novelis spokesperson Charles Belbin told the Journal. The switch to aluminum has allowed Ford to shave roughly 700 pounds off its fullsize truck's curb weight. And while official mileage ratings have not been announced, the weight loss should go a long way for improving efficiency, especially when combined other efficiency-minded improvements including better aerodynamics and new, turbocharged V6 engines.
Of course, aluminum-bodied cars are nothing new. But extensive use of aluminum in a major, best-selling product like the Ford F-150 is expected to kick off widespread use of this weight-saving material as availability rises and cost decreases. The WSJ reports that GM had originally explored the idea of moving to aluminum pickups back in 2008, but abandoned the idea due to cost concerns amid economic woes.