GM is facing a lawsuit alleging emissions cheating — but the automaker checked out all of its diesel vehicles after VW's crisis (GM)

pulse

June 2, 2017 2:54 PM

The carmaker conducted a review to ensure that it wouldn't face fines and government actions.

General Motors is fending off another class-action lawsuit, filed last week by Seattle firm Hagens Berman Sobol Shapiro, alleging that the carmaker cheated on emissions tests for its large Duramax diesel engines.

The most prevalent scenario for the alleged device to reduce emissions treatment, therefore, would be under wintertime conditions.

In a statement, GM said: "These claims are baseless and we will vigorously defend ourselves. The Duramax Diesel Chevrolet Silverado and GMC Sierra comply with all US EPA and CARB emissions regulations."

One of the issues that's emerged since VW's crisis — which resulted in billions in fines and settlements for the German automakers and effectively ended its diesel dominance for passenger cars in the US — is that there are several different types of diesel engines, with accordingly different technologies used to treat emissions.

The NOx traps that VW used for small engines were considered a breakthrough, given that they didn't require the urea-injection system that's commonplace for large engines. Americans haven't taken to diesel vehicles in the same way that Europeans have, so VW's scandal covered only about 500,000 vehicles.

Larger diesel motors are popular, however, on big trucks that are designed to tow heavy payloads, such as boats and horse trailers. GM, Ford, and Fiat Chrysler Automobiles (which is currently being sued by the government for its own alleged diesel-emissions evasions) all sell this type of vehicle and have for years.

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