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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.

New J.D. Power Initial Quality Study puts Porsche, GM in spotlight

J.D. Power and Associates has released its annual Initial Quality Study, and this year, Porsche and General Motors took the spotlight. The study, which asks new car owners to report problems experienced during the first 90 days of ownership, found that overall, the industry averages 113 problems per 100 vehicles.
Porsche managed a score of just 80 problems per 100 vehicles, while GMC took the second spot on the podium with 90. Lexus filled out the top three with 94 problems per 100 vehicles, followed by Infiniti at 95 and Chevrolet at 97. The study also looks at specific models, and found the Lexus LS to enjoy the best initial quality at 59 problems per 100 vehicles.
Interestingly enough, the report found that around two-thirds of most owner problems experienced in the first 90 days are attributable to vehicle design instead of mechanical failure. Specifically - echoing a refrain we've been hearing for the last few years - owners are having a hard time figuring out how to use the technology present in their new vehicles. Head over to the J.D. Power site for more information, or scroll down below for the company's related press release.

GM recalls select Tahoes, Yukons, Escalades for rear driveshaft issue

GM is recalling a number of its full-size SUVs due to an issue with the rear driveshaft assembly that could ultimately result in driveshaft failure. The actual number of total vehicles involved in the recall is small at just 1,789, but it’s spread out across the entire 2021 model year full-size GM vehicle lineup. That means a small number of every model is being recalled, including the Chevrolet Tahoe, Suburban, GMC Yukon, Yukon XL and the Cadillac Escalade and Escalade ESV. GM traced the issue back to certain driveshaft assemblies with ball bearings that were not properly heat treated. If theyÂ’re not properly heat treated, GM says that the balls may deform over time, causing noise and vibration. Continue to drive in this condition, and GM says the affected joint in the driveshaft assembly could seize, causing loss of drive power. However, the problem wonÂ’t present itself all at once, as GM says there will be a gradual increase of noises and vibrations before total failure. For those few owners with affected vehicles, GM says that it will replace the left and right rear driveshaft assemblies with properly-built units. Per usual with recalls, this will be done at your local dealership at no cost to the owner. If you have one of the recalled SUVs, expect to be notified mid-March. Related video: