GM Accused in Lawsuit of Using VW-Like Defeat Devices

General Motors Co. was sued for allegedly putting defeat devices in trucks to beat emissions tests, making it the fifth carmaker to be accused of diesel cheating since Volkswagen AG admitted in 2015 to flouting pollution rules.

Owners and lessees of more than 705,000 GM Duramax branded diesel trucks filed a class-action lawsuit Thursday, claiming GM installed defeat devices in two models of heavy-duty trucks from 2011 to 2016. The 190-page complaint is littered with 83 references to Volkswagen, and asserts that the environmental damage caused by each truck could surpass that of the German automaker’s vehicles.

GM’s cheating allowed its trucks to pass U.S. inspections, even while they spewed emissions two to five times the legal limit under regular driving conditions, according to the complaint filed in Detroit federal court.

“These claims are baseless and we will vigorously defend ourselves,” GM said in a statement on its website. The Detroit-based company said its diesel Chevrolet Silverado and GMC Sierra pickups comply with all U.S. Environmental Protection Agency and California Air Resources Board emissions regulations.

GM erased gains in early trading and fell as much as 3.9% after the lawsuit was filed. The shares were down 1.9%to $32.58 as of 12:57 p.m. in New York.

The complaint raises fresh questions about the credibility of diesel technology. Since allegations surfaced against Volkswagen, the automaker has committed to spending more than $24.5 billion paying fines and penalties including buybacks across North America. Many of its biggest peers have since faced lawsuits and greater regulatory scrutiny.

In the case of Fiat Chrysler Automobiles NV, drivers filed a class action alleging VW-like cheating on diesel emissions tests. Shortly thereafter, U.S. prosecutors and regulators were investigating as well, leading to a U.S. Justice Department suit this week.

Daimler AG is the target of a German probe related to diesel emissions, and French carmakers Renault SA and PSA Group are both being investigated in their home country.

NOx Pollutants “GM claimed its engineers had accomplished a remarkable reduction of diesel emissions,” attorney Steve Berman, a managing partner at Hagens Berman, said in the complaint. Berman has also represented drivers and dealerships against VW and in Fiat Chrysler’s ongoing litigation. “These GM trucks likely dumped as much excess poisonous emissions into our air as did the cheating Volkswagen passenger cars.”

Excessive emissions from the GM vehicles exposed the public to noxious levels of smog, according to the complaint.

Diesel engines, while more fuel efficient, produce greater volumes of nitrogen oxide pollutants, or NOx. During on-road testing the diesel trucks polluted at levels beyond legal limits and higher than their gasoline counterparts, according to the complaint.

Bosch Named

Supplier Robert Bosch GmbH, which was named as a co-defendant by consumers who sued VW, also is a defendant in the GM case, described in the complaint as “an active and knowing participant in the scheme to evade” emissions standards.

“Bosch takes the allegations of manipulation of the diesel software very seriously,” Linda Beckmeyer, a company spokeswoman, said in an email. “Bosch is cooperating with the continuing investigations in various jurisdictions, and is defending its interests in the litigation.”

Representatives of the Justice Department and the Environmental Protection Agency didn’t immediately respond to requests for comment.

By Kartikay Mehrotra and Ryan Beene