Enlarge Image Cummins The US Environmental Protection Agency just announced the largest voluntary recall of medium- and heavy-duty trucks to date. Diesel engine manufacturer Cummins will recall some 500,000 trucks from the 2010 to 2015 model years due to faulty emissions control systems. According to an EPA release, the defective emissions control systems cause "excess emissions of nitrogen oxides (NOx)." But unlike the infamous Volkswagen Group diesel scandal, in which defeat devices were used to cheat emissions regulations, the Cummins engines are simply fitted with defective parts. "The trucks being recalled are equipped with selective catalytic reduction (SCR) systems designed to control NOx emissions," the EPA said in an official statement. "The SCR catalysts that will be replaced through the recall were found to be less durable than is required, degrading within a few years instead of controlling NOx pollution for the regulatory full useful life of the vehicle." A Cummins spokesperson tells Roadshow the recall will be rolled out in two phases. Heavy-duty engine customers will receive notifications in August 2018, with the medium-duty engine recall to follow in March 2019. The affected vehicles range anywhere from large pickups to RVs to semi trucks. A similar, earlier recall involved roughly 232,000 Ram 2500 and 3500 pickups. Both the EPA and the California Air Resources Board (CARB) discovered the emissions problems during independent testing. Cummins verified the organizations' findings in followup testing and agreed to recall all affected engines. "This is the way it's supposed to work," spokesperson Bill Wehrum said in the EPA statement. "Our followup testing seeks to make sure that pollution controls work throughout an engine's useful life. And, if they don't, then companies step up to set things right."<doc-sep>On Tuesday, the California Air Resources Board (CARB) announced that its real-world driving tests had discovered higher-than-expected emissions levels from medium- and heavy-duty trucks with Cummins engines. Cummins cooperated with CARB and already has ways to fix the vehicles to bring their engines' emissions numbers back in line. But the company will voluntarily recall around 500,000 trucks produced between 2010 and 2015 in order to come back into compliance with federal emissions standards. You'd be forgiven for thinking this sounds like Volkswagen's 2015 diesel scandal . VW Group also had about 500,000 cars implicated in the US after a series of real-world tests found that its cars were producing emissions in excess of what Volkswagen reported to the Environmental Protection Agency. But beyond surface-level comparisons, the two cases are distinct. In this case, the emissions discrepancies in Cummins engines were caused by defective catalysts rather than by unreported software, as was the case for VW Group's diesels. Catalysts are generally used to neutralize harmful emissions like nitrogen oxide (NO X ). The Cummins catalysts, CARB reports, degraded more quickly than expected, leaving vehicles on the road still operating but without a fully functioning emissions control system. Defective hardware, not malicious intent Because the discrepancy arose from a mechanical issue rather than due to the presence of software that is expressly prohibited by the EPA, and because Cummins cooperated with CARB from the outset, the Indiana-based engine company has spared itself some significant costs. The recall is voluntary and will involve fixes that CARB and the EPA have already approved (by contrast, it took years for VW Group to get some of its fixes for some of its diesels approved). Interestingly, however, Cummins' emissions issues might never have been caught were it not for the VW Group diesel debacle. In 2016, in the wake of the diesel scandal, CARB started testing older vehicles under real-world driving conditions rather than simply testing newer vehicles. Using a Portable Emissions Monitoring System, the regulatory agency was able to discover the issue in the Cummins engine family. Advertisement "The testing confirmed that the selective catalytic reduction (SCR) systems were defective, causing emissions of NO X to exceed state and federal standards," a CARB press release noted. "The same problem was found to affect about 60 'engine families' under the Cummins name found in a wide range of vehicles, from big-rigs, to larger pickup trucks and some buses." According to Reuters, a separate recall is also underway involving "Cummins engines in around 232,000 Dodge Ram 2500 and 3500 pickup trucks made by Fiat Chrysler." The EPA opened an investigation into these trucks in 2017. In an email to Ars, Katie Zarich, an external communications manager for Cummins, wrote, "Our engines were designed to meet the emissions regulations, and we had a component challenge involving degradation of the SCR at varying rates and levels causing some of the products to produce higher emissions. We changed that component in our current products and they are operating as intended and meeting the standards."<doc-sep>
WASHINGTON/DETROIT (Reuters) - Cummins Inc has agreed to recall about 500,000 medium- and heavy-duty trucks in the United States to correct a faulty emissions control system in the engines it made for the trucks, the U.S. Environmental Protection Agency said on Tuesday. Flags fly outside the U.S. Environmental Protection Agency (EPA) at EPA headquarters in Washington, U.S., July 11, 2018. REUTERS/Ting Shen The EPA said the Cummins recall of vehicles produced between 2010 and 2015 was the largest ever voluntary recall of trucks due to emissions problems. The catalytic reduction systems were found to be less durable than required and will be replaced, it said. A spokesman for Cummins said the recall was “in the best interests of our customer and the environment.” The recall is to replace a faulty emissions control systems component that causes excess nitrogen oxides (NOx) emissions. The problem is the result of a defective part and was discovered during emissions standards compliance tests by the California Air Resources Board, which said Cummins “worked collaboratively” with the regulator on the recall. The Cummins spokesman said the recall will be rolled out in two phases, starting with heavy-duty trucks in August and medium-duty trucks next March. A previous recall that is underway involves Cummins engines in around 232,000 Dodge Ram 2500 and 3500 pickup trucks made by Fiat Chrysler Automobiles NV. The EPA said the problem does not involve illegal software known as “defeat devices,” which increase the effectiveness of emissions filters to mask pollution levels during tests. Volkswagen AG VOWG_p.DE has been found guilty of using such software to pass U.S. emissions tests in the "dieselgate" scandal which came to light in 2015. Audi AG’s Chief Executive Rupert Stadler was suspended after his arrest in mid-June as part of a broader probe into emissions cheating at the premium brand, which is part of the VW group. Stadler has appealed to a court to be released from custody.