WASHINGTON/DETROIT—Cummins Inc has agreed to recall about 500,000 medium- and heavy-duty trucks produced between 2010 and 2015 to correct a faulty emissions control system part that degrades and allows too much nitrogen oxide pollution, the U.S. Environmental Protection Agency said on Tuesday.
The EPA said the Cummings recall was the largest ever voluntary recall of trucks due to emissions problems. The catalytic reduction systems in the trucks were found to be less durable than required and will be replaced, it said.
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 latest 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 regulators, the EPA said.
The agency said the problem does not involve illegal software known as “defeat devices,” which increases the effectiveness of emissions filters to mask pollution levels during tests.
Volkswagen AG has been found guilty of using such software to pass U.S. emissions tests in the “dieselgate” scandal which came to light in 2015.
By David Alexander and Nick Carey