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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 removes start/stop from full-size trucks and SUVs with V8 engines

GM is removing start/stop technology from a number of its popular full-size SUVs due to the ongoing chip shortage. This follows the removal of cylinder deactivation technology from some of its trucks, which was also due to the chip shortage. GM Authority first reported the news, but we’ve just confirmed everything with a GM spokesperson.  The following 2021 model year vehicles will be affected: Chevy Tahoe, Chevy Suburban, GMC Yukon, Cadillac Escalade, Chevrolet Silverado 1500 and GMC Sierra 1500. Only versions of those vehicles built with the 5.3-liter V8 or 6.2-liter V8 and mated to the 10-speed automatic will have the tech removed from them. Only vehicles manufactured on or after June 7 will be affected. “By taking this measure, it will enable us to continue production of our high-demand full-size SUV and pickups as the industry continues to rebound and strengthen,” GM said in a statement. Those who ultimately buy one of these vehicles without start/stop technology will receive a $50 discount off MSRP for their troubles. Losing this fuel-saving tech could be a big negative for some, but we know many folks turn it off anyway. Not having to press the button to deactivate start/stop every time could actually be a positive if youÂ’re part of the camp who does that already. 2021 Cadillac Escalade Sport Platinum View 27 Photos On the downside, GM says “most of the affected vehicles will experience a minor reduction in fuel economy.” We donÂ’t have revised window stickers in hand to know how each model will be affected, but any 1 mpg reduction will be rather impactful for vehicles rated as low as these trucks already are. Any reduction will be seen in the city mpg rating, so take the kind of driving youÂ’re going to be doing into account before purchasing. When it comes to greenhouse gas compliance rules, GM says it doesnÂ’t foresee this impacting the companyÂ’s average fleet score. It also intends to begin adding start/stop back to these models as soon as possible, but there will be no retrofit effort made to fit the tech to vehicles already built without it. “Our supply chain organization continues to make strides working with our supply base to mitigate the near-term impacts of the semiconductor situation,” GMÂ’s statement reads. “GM continues to leverage every available semiconductor to build and ship our most popular and in-demand products, including our highly profitable full-size trucks and SUVs for our customers.

Driving a 1964 Volkswagen Beetle, and the 2021 Kia K5 arrives | Autoblog Podcast #634

In this week's Autoblog Podcast, Editor-in-Chief Greg Migliore is joined by Road Test Editor Zac Palmer and News Editor Joel Stocksdale. They start with what they've been driving this week, including the 2020 GMC Sierra 1500 diesel, 2020 Volkswagen Atlas Cross Sport and a 1964 Volkswagen Beetle. They move on to the news, covering the 2021 Kia K5, Geneva Motor Show (canceled again), Maserati's new engine and a new extended reality experience here at Autoblog. Finally, the guys spend some money for a listener who just had twins. Autoblog Podcast #634 Get The Podcast iTunes – Subscribe to the Autoblog Podcast in iTunes RSS – Add the Autoblog Podcast feed to your RSS aggregator MP3 – Download the MP3 directly Rundown Cars we're driving 2020 GMC Sierra 1500 AT4 diesel 2020 Volkswagen Atlas Cross Sport 1964 Volkswagen Beetle 2021 Kia K5 Geneva Motor Show cancelled Maserati engine Extended Reality with the Mustang Mach-E Spend your money Feedback Email – Podcast@Autoblog.com Review the show on iTunes Related Video: