What is the GM Diesel Truck Fuel Pump Defect?

Consumers who own vehicles installed with a Bosch CP4 fuel injection pump may be affected by a GM diesel truck fuel pump defect.

What is the GM Diesel Truck Fuel Pump Defect?

The GM diesel truck fuel pump defect is reportedly due to an incompatibility between the CP4 fuel injection pump and the Duramax engines installed in these vehicles, as well as an incompatibility between the pumps and American fuel. According to lawsuits regarding the defect, GM may have chosen that injection pump as a cost-saving measure, while knowing that they were incompatible.

It would be difficult for the defendants to claim they had no knowledge of the problem, as they claimed in an earlier lawsuit. The Bosch C4 pump was first developed prior to 1993, when the U.S. Environmental Protection Agency mandated that domestic refineries reduce the amount of sulfur in its diesel fuel from 5000 parts per million (ppm) to 500.

Sulfur is a naturally occurring substance in crude petroleum, and is one of the primary causes of soot. Furthermore, high sulfur content makes it more difficult for emissions control systems to work properly. The problem – of which automakers must surely have been aware – is that when sulfur is removed from diesel, it loses its lubricity. 

In 2007, the Truck and Engine Manufacturers Association warned the industry that such low-sulfur diesel fuel was incompatible with European-designed fuel systems. The problem was exacerbated in 2007, when the EPA mandated the reduction of sulfur levels for domestically-produced diesel fuel to no more than 15 ppm.

The Bosch CP4 pump was not built to be compliant with American fuel standards. These pumps are built for European fuel. According to plaintiffs in several GM lawsuits, when a Bosch CP4 pump is used with American fuel, it is not lubricated enough and is forced to run dry. This causes the pump to slowly destroy itself through metal-on-metal friction as reported by Car Complaints.

The friction results in small metal shavings being worn off and deposited throughout the fuel injection system and engine, leading to failure. First, the defective fuel pump may suddenly fail with no warning.

This diesel fuel pump failure may then cause the total fuel injection system and engine to fail as well. Unexpected engine failure while the vehicle is in motion may result in car accidents or other dangerous events.

This multi-system failure also results in incredibly expensive repairs. According to some reports, repair costs may be as much as $10,000. Additionally, these pricey repairs will not fix the root of the problem.

What Vehicles Are Affected by This Defect?

Millions of Ford and GM trucks may be installed with the defective fuel pump. Affected models include:

• 2011–present model year Ford pickups with 6.7L Power Stroke engines
• 2011–2016 2500HD Silverado 6.6L V8 Duramax Diesel Trucks with LML engines
• 2011–2016 3500HD Silverado 6.6L V8 Duramax Diesel Trucks with LML engines
• 2011–2016 2500HD Sierra 6.6L V8 Duramax Diesel Trucks with LML engines
• 2011–2016 3500HD Sierra 6.6L V8 Duramax Diesel Trucks with LML engines
• 2010–2011 Chevrolet Express van with Duramax LGH engines
• 2010–2011 GMC Savana van with Duramax LGH engines
• 2010–2011 GMC Sierra trucks with RPO ZW9 with Duramax LGH engines
• 2011–2012 2500HD 3500 Silverado 6.6L V8 Duramax Diesel Trucks with LGH engines
• 2011–2012 2500HD 3500 Sierra 6.6L V8 Duramax Diesel Trucks with LGH engines

GM Diesel Truck Fuel Pump Defect Lawsuits

According to several of the recent lawsuits filed against General Motors regarding the GM diesel truck fuel pump defect, the company may have been aware of the incompatibility between the pump and Duramax engines and American fuel.

Plaintiffs say that automakers have blamed consumers for using contaminated fuel, and have refused to honor the terms of warranties, as such damage caused by such fuel system contamination is not covered. Instead, in some cases, defendants have issued what they call “disaster preventer” or “bypass” kits. The purpose of these kits is reportedly to divert the lubricating fuel back to the tank for filtration before it goes into the engine itself. However, those who have been affected state that the metal shavings remain in the fuel as it returns to the engine.

Plaintiffs in the lawsuits are seeking damages for the cost of repairs, as well as loss of vehicle use, and inconvenience. If you own one of the affected models, you may qualify to join or file a class action lawsuit to pursue compensation.

Join a Free GM Fuel Pump Class Action Lawsuit Investigation

You may be eligible to join this GM fuel pump class action lawsuit investigation if you bought one of these GM vehicles:

• 2011-2016 Chevrolet Silverado 2500HD (6.6L V8 Duramax LML engine)
• 2011-2016 Chevrolet Silverado 3500HD (6.6L V8 Duramax LML)
• 2011-2016 GMC Sierra 2500HD (6.6L V8 Duramax LML)
• 2011-2016 GMC Sierra 3500HD (6.6L V8 Duramax Diesel Trucks LML)
• 2010-2011 Chevrolet Express (6.6L Duramax LGH engine)
• 2010-2011 GMC Savana (6.6L Duramax LGH engine)
• 2010-2011 GMC Sierra Chassis Cabs/Pickup Box Delete (6.6L Duramax LGH engine)
• 2011-2012 Chevrolet Silverado 2500HD and 3500 (6.6L V8 Duramax LGH engine)
• 2011-2012 GMC Sierra 2500HD and 3500 (6.6L V8 Duramax LGH engine)

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