2007 Gmc Yukon Denali Black Suv on 2040-cars

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GM under fire from safety advocates over braking problem caused by recall fix

Safety experts are lambasting General Motors over what they say is the automaker’s slow notification of owners of certain 2019 sedans and trucks that a recall fix could cause power braking to fail and increase the risk of a crash, the Detroit Free Press reports.  GMÂ’s original recall in December targeted about 550,000 Cadillac CT6 sedans and Chevrolet Silverado 1500 and GMC Sierra 1500 pickups, all from the 2019 model year, over potentially defective electronic stability control and antilock brakes. In that case, GM said the errors would not show up as a diagnostic warning on the instrument cluster. But after GM had done recall work on 162,000 vehicles, about 1,700 owner have complained that their power brakes didnÂ’t work after they had the recall done and then used the OnStar app to start their vehicle. GM then issued a supplemental fix for customers whoÂ’d already had their vehicles serviced. In this case, a diagnostic warning should illuminate saying either “Service Brake Assist” or “Service ECS,” which GM says is a signal that a customer should not drive the vehicle and instead call their dealer, which will tow the vehicle and have it repaired. Safety advocates say the automaker hasnÂ’t gone far enough to protect customers. “The fact that you could potentially start a vehicle and not have brakes is a pretty risky proposition,” Sean Kane, president of the Safety Research and Strategies, which works on auto issues for plaintiffs and governmental organizations, told the Freep. “The fact that they wouldnÂ’t notify owners (sooner) is pretty stunning.” GM told the Freep it was required to notify the National Highway Traffic Safety Administration and file paperwork before it notified customers about the original recall, which was made Dec. 12. It then had to investigate and resolve the problem created by its original recall fix before alerting customers. GMÂ’s call center and dealers are contacting the remaining 900 customers who havenÂ’t yet had the update made to the original recall repair. GM also hired a vendor to send recall letters to the 550,000 customers affected by the original recall notifying them about the update. There are no known injuries or deaths related to the problem. Read the Freep story here.

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!"

Canada opens probe into 250,000 GM pickups, SUVs over brake performance

Transport Canada, the auto safety regulator, has opened a probe into braking issues in nearly 250,000 General Motors full-size pickups and SUVs after U.S. officials launched a similar probe last year, the agency said on its website. The U.S. National Highway Traffic Safety Administration (NHTSA) in November into 2.73 million U.S. 2014-2016 model year SUVs and pickups after receiving 487 reports of hard brake pedal effort accompanied by extended stopping distance that were attributed to deterioration of the engine-driven brake assist vacuum pump. Transport Canada's probe covers 249,700 2015 through 2017 model year vehicles including the Cadillac Escalade, Chevrolet Suburban, Chevrolet Tahoe and GMC Yukon as well as 2014-2017 Chevrolet Silverado LD and GMC Sierra LD vehicles. The U.S. agency said it had reports of nine incidents of vehicles incurring damage as a result of colliding with another vehicle or fixed object at low speeds and reports of two injuries. NHTSA said if the pump fails to operate, the amount of brake power assist can be significantly reduced, extending vehicle stopping distance. The NHTSA sent GM an information request in a Feb. 7 letter. A GM spokesman said he had no update on the investigation. Reporting by David Shepardson; editing by Jonathan Oatis