Lawsuit Alleges Emissions Cheating on LML Duramax Diesel Engine
GM Denies Allegations and Will “Vigorously” Defend Itself
It seems as soon as the Volkswagen TDI emissions case breached the dam, there was a flood of allegations, lawsuits, investigations, sales holds, delays, and changes of plans with new diesel models from nearly every manufacturer. The latest diesel model to face allegations of emissions cheating is General Motors’ popular LML 6.6L Duramax diesel V-8 engine, offered in 2011–2016 Chevrolet Silverado and GMC Sierra HD pickups. The lawsuit was filed by the firm Hagens Berman Sobol Shapiro, a Seattle-based law firm with offices across the country. The firm was also involved in the Volkswagen emissions case, as well as the Fiat Chrysler Automobiles (FCA) EcoDiesel case. The firm is well-versed in automotive litigation, also being involved in the Ford Mustang Shelby GT350 overheating case, as well as the Tesla Autopilot case.
Reading through the lawsuit, the firm alleges the exhaust system design of the LML was designed to deliberately work around regulations by placing the selective catalyst reduction (SCR) system ahead of the diesel particulate filter (DPF). The suit claims this design optimizes power output while making the truck perform favorably under lab conditions for cold start emissions. However, the suit alleges this design increases real-world NOx emissions and would require more aggressive SCR fluid dosing and would require more frequent and aggressive regeneration cycles of the DPF, increasing fuel consumption and decreasing power. The suit further claims collusion with Bosch, the supplier of the fuel system for the LML Duramax, claiming the supplier had full knowledge of the software scheme and operating parameters of the engine controls.
Potentially 700,000 trucks between the 2011¬–2016 model years are affected. Like FCA with the EcoDiesel case, GM says it will “vigorously” defend itself against the allegations. The NOx emissions of the trucks are alleged to be two to five times the allowable levels. This is much less than the 40x NOx emissions found with the Volkswagen TDI engines. In our experience, truck owners are more concerned about capability and economy than emissions, a contrast to diesel passenger car buyers, many of whom bought diesels under the auspices of them being more environmentally friendly. What do you think? Will GM ultimately be exonerated in this case, or will this be “dieselgate” all over again?
Source: Reuters, Hagens Berman Sobol Shapiro