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  • Lawsuit Against GM Alleges 2011-2016 6.6L Duramax Diesel Incompatible with U.S. Fuel

Lawsuit Against GM Alleges 2011-2016 6.6L Duramax Diesel Incompatible with U.S. Fuel

Class-Action Suit Relates to CP4 High-Pressure Fuel Pump

Aug 8, 2019
Photo 2/4   |   2011 Chevrolet Silverado 2500HD Front End In Motion 2

General Motors is facing a class-action suit filed in federal court yesterday, which alleges that the high-pressure fuel injection pump on 2011-2016 6.6L Duramax diesel engines is incompatible with American diesel fuel.

According to the Detroit News, the reduced lubricity of U.S. diesel fuel can cause air pockets to form as it passes through the injection pump, damaging the pump and introducing metal shavings into the engine. The suit originally represented eight plaintiffs, but it estimates that the total number of impacted drivers is at least in the tens of thousands.
Photo 3/4   |   2011 Chevrolet Silverado 2500HD Front Right View 2

Included in the suit are the 2011-2016 Chevrolet Silverado 2500HD and 3500HD and GMC Sierra 2500HD and 3500HD, all of which are powered by the 6.6L Duramax LML engine. The 2010-2011 Chevrolet Express and GMC Savana, 2010-2011 GMC Sierra box-delete, and certain configurations of the 2011-2012 Chevrolet Silverado HD and GMC Sierra HD are also involved, powered by the 6.6L Duramax LGH.

Failures to the engine's CP4.2 injection pump are relatively well documented, especially when it encounters low-quality diesel fuel. The enthusiast scene is quick to convert over to CP3 injection pumps or add additional fuel filtration and purification. Other potential remedies include cetane boosters that improve the lubricity of diesel fuel.
As to whether GM is legally responsible for those anecdotal injection pump failures, we'll just have to let the courts decide.
Source: Detroit News
Photo 4/4   |   2011 Chevrolet Silverado 3500HD DRW LT In Motion 2