By Greg Gardner

"A Seattle law firm alleges Fiat Chrysler and Cummins, an Indiana-based engine manufacturer, intentionally misled owners of Dodge Ram diesel-powered heavy-duty pickup trucks about their emission levels.." Posted By Greg Gardner , Detroit Free Press 5:28 p.m. EST November 14, 2016

The class action case was filed Monday in federal court in Detroit by Hagens Berman Sobol Shapiro. Four plaintiffs are named in the complaint, but Hagens Berman seeks to bring thousands of other owners into the case.

They allege that the particulate emissions from the trucks were greater than FCA US advertised. Hagens Berman contends the trucks' emissions caused catalytic converters to wear out more quickly, resulting in the vehicle burning fuel at a higher rate.

“The sheer level of fraud and concealment between Chrysler and Cummins is unconscionable, and we believe we have uncovered a deeply entrenched scheme,” said Steve Berman, managing partner of Hagens Berman, in a statement.

In response, FCA said it is reviewing the complaint, adding "based on the information available to it, FCA US does not believe that the claims brought against it are meritorious. We will contest this lawsuit vigorously."

Separately Fiat Chrysler is cooperating with a recall that the U.S. Environmental Protection Agency and California Air Resources Board demanded for 2013 through 2015 model year Ram 2500 pickup trucks with 6.7-liter Cummins diesel engines. The agencies found that moisture can cause deactivation of the catalyst reduction system, causing excess nitrogen oxide emissions.

But in August the automaker sued Cummins for $60 million Fiat Chrysler attorneys said the company has already spent to repair the emission systems on about 42,000 of the diesel trucks.

The Hagens Berman case seeks to broaden the issue to include owners of Ram 2500 and 3500 diesels going back as far as the 2007 model year. The lawsuit also charges that much of what FCA and Cummins did was similar to Volkswagen, which put devices in about 11 million diesel cars meant to deliberately cheat on emission tests.

The German automaker is facing penalties up to $19.5 billion. Similar charges have been made against Mercedes-Benz, but that company has denied them.

The recall of the Ram heavy-duty diesels is different from the Volkswagen case.

FCA and Cummins contend the problem involves a component that didn't function as designed and that there was no intention to mislead regulators or consumers. They disagree over which of them is responsible.