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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.

Next-gen GMC Sierra spied with diesel power

The next generation of GM trucks is arriving soon, and we're expecting a huge leap forward over the current lineup. The Chevy Silverado and the GMC SIerra sell extremely well, but haven't done much to move the segment forward in a long time. The Ford F-150 has an all-aluminum body and turbocharged V6 power. The Ram 1500 gained a diesel and coil spring suspension. These spy shots show that diesel may be in the cards for GM. Some quick shots and copious use of flash show what is most likely a tank for diesel exhaust fluid and a diesel particulate filter, both necessary equipment for any modern diesel. It's unclear what form factor that engine will come in, though GM has a number of engines to choose from, including the 2.8-liter inline four that's found in the Colorado and Canyon, though that may be a little light duty for the Silverado and Sierra. Other rumors surrounding the trucks suggest a move to an aluminum cab while retaining a steel bed. That seems like a reasonable move for GM, even if the company was attempting to shame Ford for its move to aluminum a few years ago. Look for more news as early as the Detroit Auto Show in January. Related Video: Featured Gallery 2019 GMC Sierra spy shots View 21 Photos Image Credit: Spied Bilde Spy Photos Chevrolet GMC Truck

Is your new-car warranty good at the race track?

We've all heard the horror stories. Your buddy knows a girl that was dating a guy whose best friend's brother once broke his brand-new, recently purchased performance car while making runs at a drag strip or laps at a track day, and the manufacturer wouldn't cover the repair under warranty. True story? Urban legend? Complete crap? Yes, no, maybe. One thing's for sure: Automotive warranties have always come with caveats. In 1908, an ad in the Trenton Evening Times clearly stated: "All Ford Cars Guaranteed for One Year." Although it changed over time, by 1925 the Ford New Car Guarantee only covered 90 days on material and 30 days on labor, and it clearly stated that that there was "No guarantee whatever on Fan Belts, Glass, Bulbs, Wiring, Transmission, Bands, Hose Connections, Commutator Shells, Rollers, Spark Plugs or Gaskets." Whether or not Ol' Henry would pay to fix your Model T if you broke it shaving a tenth off your lap time at the local board track seems to be lost to history. We're guessing no. But what about today? Do new-car warranties in 2017 cover cars when they are driven on race tracks? We researched the warranties of 14 auto brands to find out, and the answer is yes, no, maybe, depending on the brand, in some cases the model, and whether or not your car is modified from stock. Acura has been out of the high-performance car game for a number of years, but jumps back into the party in 2017 with its hybrid-powered $173,000 NSX supercar. And Acura's warranty, as well as Honda's, clearly states that it does not cover "the use of the vehicle in competition or racing events." View 33 Photos So we asked Sage Marie, Senior Manager of Public Relations for Honda and Acura. "If the car is stock, the warranty covers it on a track just as it does on the street. No question," he told us. "However, if the car is modified, say with slick tires or other components that would put higher stresses on the vehicle's parts and systems, then we would have to investigate the circumstances further." Marie went on to say the same would be true for any Acura model or Honda vehicle, including the new 2017 Honda Civic Si. This became a common theme. Chevrolet actually started this practice with the fifth-generation Camaro on the high-performance ZL1 and Z/28 models.