1996 Chevrolet C/k 3500 Silverado on 2040-cars

Auto blog

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 recalls 3.8 million vehicles in North America due to braking issue

WASHINGTON — General Motors Co said Wednesday it was recalling 3.46 million U.S. pickup trucks and SUVs to address a vacuum pump issue that could make braking more difficult and that has been linked to 113 accidents and 13 injuries. The recall covers 2014-2018 model year vehicles, including some Cadillac Escalade, Chevrolet Silverado, Chevrolet Tahoe, GMC Sierra, Chevrolet Suburban and GMC Yukon vehicles. In late June, GM recalled 310,000 vehicles in Canada for the same issue. GM did not immediately explain why the Canadian recall occurred more than two months before it called back the vehicles in the United States. The recall was triggered because the amount of vacuum created by the vacuum pump may decrease over time, GM told the National Highway Traffic Safety Administration (NHTSA) in documents posted on Wednesday. The NHTSA opened a preliminary investigation into the issue last November, and said it had reports of nine related crashes and two injuries. It provided GM in July with additional field reports that prompted the automaker to open an investigation. GM said it could affect braking in "rare circumstances." The NHTSA said in a statement the "vehicles may experience brake boost failure, which would require increased brake pedal effort, leading to a hard brake pedal feel, and potentially increased stopping distance." GM said dealers will reprogram the electronic brake control module to improve how the system utilizes the hydraulic brake boost assist function when vacuum assist is depleted. GM said the vacuum assist pump, which is lubricated with engine oil that flows into the pump through a filter screen, can in some cases lose effectiveness over time, as debris such as oil sludge can accumulate on the filter screen. GM told NHTSA that prior model years used a different brake assist system design, and vehicles manufactured after 2018 were not equipped with the affected pump design. Separately, GM said on Wednesday it is recalling 270,000 additional U.S. vehicles in three smaller recalls, including 177,000 2018 Chevrolet Malibu cars with 1.5L turbo engines because an error in the engine control module software may result in the fuel injectors being disabled.

Personal testimonies show real-world effect of plugging in with Chevy Volt

At this point, there are tens of thousands of individual stories about what it's like to live with a Chevrolet Volt. But it also remains informative to take a look at one of these in depth. For example, one Atlanta-area Volt owner says he's cut his cents-per-mile ownership costs by almost 40 percent compared to his previous car primarily because of his ability to drive almost all the time on electric power. Jeffrey Cohen told Clean Technica that he put about 14,000 miles on his Volt extended-range plug-in hybrid for the year that ended October 2013, and that more than 92 percent of those were on electrons. He estimates his "lifetime" miles per gallon rating at a whopping 384 mpg, a figure pushed upward by the fact that he installed a Level 2 charger at home while his employer added an external 110-volt charger at work. Cohen is spending 45 cents a mile for his car, compared to 73 cents in his Infiniti M35. As a result, he's spending 45 cents a mile for his car, compared to 73 cents a mile with his prior vehicle, an Infiniti M35. About two-thirds of those Volt costs are for the $349-a-month lease payments, while 15 percent is insurance, 11 percent is for the charger and seven percent for the gas and electricity that actually powers the car. Helping lower that last figure is an overnight electricity rate that's about 10 percent of Cohen's daytime rate. Chevy parent General Motors hopes such testimonies will re-trigger sales for the Volt in 2014. Last year, GM sold 23,094 Volts, down 1.6 percent from 2012. We expect our readers have similar stories they'd like to share in the Comments. Related Gallery 2011 Chevrolet Volt: Review View 22 Photos News Source: Clean TechnicaImage Credit: Lead image: AP Photo/Jae C. Hong Green Chevrolet GM Electric running costs