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GM exploring ways to raise half-ton Duramax diesel tow rating

Lots of truck owners cheered when GM announced fuel economy numbers for the 2020 Chevrolet Silverado with the 3.0-liter Duramax diesel inline-six. Even after Ram let loose its EPA mileage ratings for the 2020 Ram 1500 EcoDiesel, the Chevy oil-burner still took the trophy. The victory was years in the making, GM engineers spending an entire four-year development cycle refining the LM2 Duramax to increase mileage. The tradeoff, as well all know by now, is towing; the Duramax in half-ton duty pulls a maximum 9,300 pounds in the Silverado. Rivals across town can do more, the Ford F-150 PowerStroke rated at 11,500, the Ram 1500 EcoDiesel game to pull 12,560. GM engineer John Barta told Muscle Cars & Trucks that more hauling chops could be on the way, explaining, "We’re actually looking at upgrading some of the materials around (the engine bay) to see if we can maybe raise our tow rating." Engine bay materials are at issue due to thermal complexities underhood. John Barta, GM's assistant chief engineer of diesel engine controls, said the Duramax's inline-six configuration allowed engineers to get emissions hardware like the combined selective catalytic reduction, diesel oxidation catalysts, and diesel particulate filter unit closer to the engine, where it heats up quicker, getting emissions down quicker. But that filter puts another heat source in those confines, enforcing a cap on the tow rating to keep the engine and other systems from overheating. "If you look under the hood," he said, "youÂ’ll see a significant amount of silver ‘moon tapeÂ’ around to make sure things arenÂ’t getting overheatedÂ… if we were to go up in higher towing, which we can, we start impacting the possibility of deteriorating some of the components.” There isn't much space for more grille, so swapping for a better grade of "moon tape" or a different kind of material could reduce engine bay heat, extracting a higher tow rating in the process.  It's important to note a point Barta's been making for months about the Duramax figures, though. "Even though itÂ’s nice to brag about big numbers, in reality, light duty customers are not towing that large with their trucks," and, "We do know that (95 percent) of our light duty customers donÂ’t tow over 9,000 pounds." On our First Drive of the 2020 Silverado diesel we called out the tow rating, but emphasized that the Chevy and GMC have more important challenges to overcome.

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.

Coronavirus shakes up America's truck market: GM outselling Ford and Ram

FCA, Ford and General Motors joined the rest of the U.S. auto industry in taking heavy volume hits due to coronavirus-related shortages of both cars and customers. The saying goes that a rising tide lifts all boats; it stands to reason, then, that a falling one would have the opposite effect.  However, as we learned Thursday, the automotive market can behave in unpredictable ways. While the F-Series remained the best-selling nameplate in Q1, GM's full-size trucks are now outselling Ford's again for the first time in years, and with this upward thrust from the General, FCA's Ram was unceremoniously booted out of a hard-earned second place.  While late-March sales declines hit just about every major automaker in one way or another, the model-by-model results weren't nearly so uniform. And because the market tends to be a zero-sum game, for every winner, there generally has to be a loser.  In this case, that winner was GM, and its rise had to come at the expense of another automaker, in this case, Ford. F-Series sales dropped 13.1 percent in the first quarter of 2020, while sales of GM's full-sized Silverado and Sierra surged nearly 28% in the same period. FCA's Ram lineup managed a steady-as-she-goes 7% increase. All-in, GM finished the quarter with 197,743 full-size trucks sold to Ford's 186,562. Here's the full breakdown: Ford F-Series: 186,562  Chevrolet Silverado*: 144,734 Ram P/U: 128,805 GMC Sierra: 53,009 *includes 1,036 Medium Duty sales Things are a but murkier in the midsize segment, where the Chevy Colorado slipped 36% to just 21,430 units sold — just a few hundred better than the slow-selling Ford Ranger's Q1 numbers. The GMC Canyon experienced an almost identical slide, finishing the quarter with just 4,483 units sold. For perspective, Jeep sold more than 15,000 Gladiators and Toyota's midsize Tacoma slipped less than 8%, finishing the quarter with nearly 54,000 sales.  We suspect this discrepancy in full- and mid-size truck sales comes from shifting incentives. Ford, GM and FCA would like to keep selling bigger trucks because there's far more profit margin built into their list prices. Even with tens of thousands of dollars in manufacturer money on the hood, big trucks still make money.  Since these automakers report quarterly, we won't get another good look at these numbers until July, but if you thought that 2019 represented the new normal for U.S. auto sales, well, think again.