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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.

Chevy says not to look at the 2019 Silverado's fuel economy rating

The 2019 Chevy Silverado is hitting dealerships soon, and one of the most notable changes for the new full-size pickup is the addition of a 2.7-liter turbocharged inline-four. The engine replaces the naturally-aspirated 4.3-liter V6 in volume consumer models like the Silverado LT and promises more power, less weight and — most importantly — better fuel economy. The thing is, the gains in efficiency haven't been as dramatic as some might have hoped, especially when stacked up against competitors from Ford and Ram. As Automotive News reports, GM's response is a little murky. First, let's talk numbers. We're pulling all figures from FuelEconomy.gov, the official U.S. government source for fuel ratings. Fuel economy numbers on trucks vary greatly based on a number of factors. Bed and cab configuration play a part, but so does a four-wheel-drive system. You also have to factor in tires, transmissions, rear-axle gearing, hybrid systems and cylinder deactivation. Things like that can make the difference between best- and worst-in-class. The EPA's website doesn't give enough information a lot of the time, so there's really no easy way to compare apples-to-apples. First, take a look at the ratings for the 2019 Silverado. A 2.7-liter model with two-wheel drive is rated 20 city, 23 highway and 21 combined. That's both better and worse than a two-wheel drive 2018 Silverado with the 4.3-liter V6 (18 city, 24 highway and 20 combined). The updated 2019 Silverado with a 4.3-liter V6 has yet to be rated. With less weight and a smaller engine, many hoped Chevy would make bigger gains. It's unusual to see any decrease in a fuel economy metric these days. GM says that it's not done tuning the new 2.7-liter engine, so fuel economy could theoretically increase. Expanding further, a V8-powered 2019 Silverado (17 city, 24 highway and 19 combined) actually gets better highway fuel economy than a turbocharged four-cylinder powered truck in certain configurations, even if the latter has a better overall average. But that's only with two-wheel drive, the 8-speed transmission and cylinder deactivation. A Silverado with the 5.3-liter V8 and a 6-speed automatic is rated at 15 city, 22 highway and 17 combined. The biggest issue with the Silverado 2.7-liter doesn't come from within GM itself but from Ford and Ram. GM cites the Ford F-150 with the 3.3-liter V6 and the Ram 1500 with the 3.6-liter V6 as the closest competitors to its new 2.7-liter inline-four.

2014 Corvette Stingray meets Tesla Model S in drag strip showdown

They come from two different worlds and have little in common. The Tesla Model S P85 is the sportiest version of this paradigm-punching sedan from California, while the 2014 Corvette Stingray Z51 is a performance-enhanced version of Michigan's recently-updated sports car stalwart. The West Coast car seats five adults and eats electrons like Popeye eats spinach, the Easterner has two passenger places and, surprisingly, sips gasoline like one might bourbon. An attribute they do happen to share is extreme quickness. This similarity is all the excuse Drag Times needed to set the vehicles beside each other at the Palm Beach International Raceway for a bit of mano-a-mano quarter-mile combat. Fortunately enough, cameras were rolling for each of two bouts down the blacktop and the results recorded for our edification and enlightenment. The winner? We won't spoil it for you, but let's just say it's really, really close. How close? Scroll below and watch the video for yourself. Just be warned, the results may surprise you. This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings.