The EPA said it discovered the “defeat devices” through testing that it began performing after the 2015 Volkswagen diesel emissions scandal.  -  HDT graphic

The EPA said it discovered the “defeat devices” through testing that it began performing after the 2015 Volkswagen diesel emissions scandal.

HDT graphic

    Cummins must recall more than 600,000 Ram 2500 and Ram 3500 pickup trucks equipped with its diesel engine as part of a record-setting $1.675 billion settlement deal with the Environmental Protection Agency and the California Air Resources Board.

    That proposed settlement was first announced last month. The government said Cummins violated the Clean Air Act and California law by installing software “defeat devices” on hundreds of thousands of diesel engines in Ram trucks that allegedly circumvented emissions testing and certification requirements.

    On Jan. 10, more details on the settlement were released as the engine maker signed consent decrees.

    In the settlement, Cummins denies the allegations in the complaints and does not admit any liability in connection with them. In a statement, the company said it "has seen no evidence that anyone acted in bad faith and does not admit wrongdoing."

    On top of the $1.675 billion civil penalty, Cummins will spend more than $325 million to remedy the violations, as well as:

    • Extend the warranty period for certain parts in the repaired recall vehicles.
    • Fund and perform projects to mitigate excess ozone-creating nitrogen oxides (NOx) emitted from the vehicles.
    • Employ new internal procedures designed to prevent future emissions cheating.

    In total, the settlement is valued at more than $2 billion. The terms of the proposed settlement with Cummins are spelled out in two consent decrees that the United States and California filed with the U.S. District Court for the District of Columbia.

    Engine Emissions Defeat Devices

    The “defeat devices” were actually software in the electronic control module of these vehicles that reduced the effectiveness of the selective catalytic reduction (SCR) system. In some normal driving conditions, the system is impacted, which increases the level of nitrogen oxides (NOx) tailpipe emissions.

    During California Air Resources Board and EPA testing, the vehicles produced compliant emission results. But at other times during actual vehicle operation, the SCR failed to adequately address the NOx emissions.

    Nearly 1 million vehicles with this software were sold in the United States from 2013 to 2023. Approximately 630,000 model year 2013 through 2019 Ram 2500 and 3500 diesel vehicles will be eligible for a software recall and extended warranty.

    Approximately 330,000 additional model year 2013 through 2023 Ram 2500 and 3500 diesel vehicles contain software that was previously undisclosed to the government but does not need to be recalled.

    The EPA said it discovered the “defeat devices” through testing at the agency’s National Vehicle and Fuel Emissions Laboratory. EPA began performing this specific type of testing after the 2015 Volkswagen diesel emissions scandal and announced that going forward it would perform additional testing “using driving cycles and conditions that may reasonably be expected to be encountered in normal operation and use, for the purposes of investigating a potential defeat device.”

    Ram Recall Program

    The settlement requires Cummins to work with Fiat Chrysler and its dealers on a vehicle recall and repair program that will remove all defeat devices from the affected 2013-2019 Ram trucks free of charge and bring the vehicles into compliance with applicable emissions standards under the Clean Air Act.

    The repair only involves software updates, no hardware changes. Cummins has already started the recall and repair program required by the settlement.

    Cummins must repair at least 85% of the 2013-2019 Ram trucks equipped with defeat devices within three years. The company also must offer a special extended warranty covering emission control system parts on 2013-2019 Ram trucks that receive the replacement software.

    The consent decree dictates that Cummins “shall use commercially reasonable efforts” to make the emission modification fix in a given vehicle within 15 days of the date the owner requests and schedules it. And it’s expected to take “reasonable steps” to ensure that the vehicle owners don’t have to wait more than 75 days for a scheduled appointment.

    Cummins also must test some of the repaired trucks over a number of years to ensure that the trucks continue to meet emissions standards over time. 

    In addition, Cummins will have to conduct dynamometer testing to demonstrate off-cycle tailpipe emissions on future 2026-2028 Ram 2500 and Ram 3500 equipped with diesel engines manufactured by Cummins.

    The violations and settlement agreement do not include:

    • Ram 1500 3.0L Eco Diesel truck, which has a Ram certified engine,
    • Other diesel vehicles and engines manufactured by Cummins, including models that may be sold outside the United States.

    Highlights of the Cummins Emissions Settlement Agreement:

    • Civil Environmental Penalty: $1.675 billion — $1.642 billion for the Clean Air Act violations and $33 million for related claims under California state law.
    • Federal NOx Mitigation: Repowering 14 road switch locomotive engines and 13-yard switch locomotive engines, as well as installing idle reduction technology on 50-yard switch engines.
    • California NOx Mitigation: A lump sum payment to CARB of slightly more than $175 million to fund mitigation actions that reduce NOx emissions in California.
    • Vehicle Recall: Recall of at least 85% of affected vehicles within three years.
    • Enhanced Testing and Corporate Compliance: Enforceable measures to prevent future violations.
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