2003 Gmc Sierra 1500 C1500 on 2040-cars

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GM resumes production of its 3.0-liter turbodiesel straight-six

General Motors temporarily stopped taking orders for trucks and SUVs equipped with the 3.0-liter Duramax turbodiesel six-cylinder engine in August 2021 due to a supplier shortage. Reports claimed the pause would last through 2021, but the engine is already back in production. Enthusiast website GM Authority learned from sources inside General Motors that the straight-six is once again coming off the assembly line at the Flint Engine Plant in Flint, Michigan. There's no official word on precisely what the problem was linked to and whether it was related to the on-going chip shortage that's wreaking havoc across the automotive industry. All we know is that the pause lasted for about two weeks. Called LM2 internally, the six is available in Chevrolet's Tahoe, Suburban, and Silverado 1500 and in GMC's version of these trucks. It's also an option in the Cadillac Escalade. It develops 277 horsepower at 3,750 rpm and a V8-like 460 pound-feet of torque at 1,500 rpm in every application, and it allows these big behemoths to post surprising fuel economy numbers. Fitted to a rear-wheel-drive Tahoe, the Duramax returns 21 mpg in the city, 28 mpg on the highway, and 24 mpg in a combined cycle, figures that make it more efficient than a Blazer. Demand for the diesel-powered trucks is relatively high. While the shortage undoubtedly took a toll on sales, the Duramax represented 8% of Suburban sales and 6% of Tahoe sales in May 2021. There are no other diesel-burning full-size SUVs available new so they have the market to themselves. On the truck side, Ram still makes the EcoDiesel available on some 1500 trims but Ford abandoned the segment. Related Video: Featured Gallery 2021 Chevrolet Tahoe RST View 24 Photos Chevrolet GMC Truck SUV Diesel Vehicles

2014 Chevy Silverado, GMC Sierra first pickups to ace updated NHTSA tests [w/video]

General Motors has just become the first pickup truck manufacturer to receive five-star overall vehicle scores in the National Highway Traffic Safety Administration's New Car Assessment Program. The updated safety standards, which went into effect in 2011, are more strenuous than the previous NHTSA curriculum and involve collecting both more and more substantial data, reflecting the improved safety inherent in newer vehicles. This feat is made more impressive by the fact that both Ford and Ram have released brand-new trucks since the new testing went into effect - GM's victory is no technicality.
The rating only applies to the redesigned, light-duty Silverado, Sierra and their upmarket variants, High Country and Denali, respectively, while only Crew Cab variants were tested. Considering that the four-door body style will make up 60 percent of GM's light-duty truck sales, the exclusion of the other variants seems reasonable.
This news is sure to be yet another feather in GM's pickup-oriented cap. Be sure to scroll down for video of the crash testing, as well as the full press release from General Motors.

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.