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GM recalls 3.8 million vehicles in North America due to braking issue

WASHINGTON — General Motors Co said Wednesday it was recalling 3.46 million U.S. pickup trucks and SUVs to address a vacuum pump issue that could make braking more difficult and that has been linked to 113 accidents and 13 injuries. The recall covers 2014-2018 model year vehicles, including some Cadillac Escalade, Chevrolet Silverado, Chevrolet Tahoe, GMC Sierra, Chevrolet Suburban and GMC Yukon vehicles. In late June, GM recalled 310,000 vehicles in Canada for the same issue. GM did not immediately explain why the Canadian recall occurred more than two months before it called back the vehicles in the United States. The recall was triggered because the amount of vacuum created by the vacuum pump may decrease over time, GM told the National Highway Traffic Safety Administration (NHTSA) in documents posted on Wednesday. The NHTSA opened a preliminary investigation into the issue last November, and said it had reports of nine related crashes and two injuries. It provided GM in July with additional field reports that prompted the automaker to open an investigation. GM said it could affect braking in "rare circumstances." The NHTSA said in a statement the "vehicles may experience brake boost failure, which would require increased brake pedal effort, leading to a hard brake pedal feel, and potentially increased stopping distance." GM said dealers will reprogram the electronic brake control module to improve how the system utilizes the hydraulic brake boost assist function when vacuum assist is depleted. GM said the vacuum assist pump, which is lubricated with engine oil that flows into the pump through a filter screen, can in some cases lose effectiveness over time, as debris such as oil sludge can accumulate on the filter screen. GM told NHTSA that prior model years used a different brake assist system design, and vehicles manufactured after 2018 were not equipped with the affected pump design. Separately, GM said on Wednesday it is recalling 270,000 additional U.S. vehicles in three smaller recalls, including 177,000 2018 Chevrolet Malibu cars with 1.5L turbo engines because an error in the engine control module software may result in the fuel injectors being disabled.

Submit your questions for Autoblog Podcast #321 LIVE!

We're set to record Autoblog Podcast #321 tonight, and you can drop us your questions and comments regarding the rest of the week's news via our Q&A module below. Subscribe to the Autoblog Podcast in iTunes if you haven't already done so, and if you want to take it all in live, tune in to our UStream (audio only) channel at 10:00 PM Eastern tonight.
Discussion Topics for Autoblog Podcast Episode #321
Unibody Ford Ranger replacement

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!"