What Causes the Duramax Fuel Pump to Fail?

The Duramax fuel pump found in certain GM vehicles may fail due to metal particulates damaging the fuel system.

What is the CP4 Fuel Pump?

Fuel pumps
are components of an engine that draw fuel from the gas tank into the fuel injection system. Not all engines rely on fuel pumps, as some older engines use gravity to get fuel to the engine.

Some vehicles have two fuel pumps, a high pressure and a low pressure pump. The low-pressure pump is found in the fuel tank while the high-pressure fuel pump is found near the engine. Together, these pumps get fuel from the gas tank to the fuel injection system in the engine.

The Bosch CP4 fuel pump is a high-pressure fuel pump that has been used in several GM vehicles that contain a Duramax engine. The CP4 Fuel Pump may be found in numerous GM vehicles from model years 2010 to 2016, including:

• 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)

What Causes the Duramax Fuel Pump to Fail?

Unfortunately, the Duramax CP4 fuel pump may be prone to failure. A lack of lubricants in the pump can cause friction within the pump. Additionally, modern diesel fuel has removed sulfur which destroys the natural lubricants in fuel that would help with this issue.

Prolonged friction in the fuel pump causes metal components to rub together and produce metallic particles. These particles can reportedly be distributed throughout the fuel injection system, causing catastrophic engine failure. In some cases, the pump itself may seize and burst due to failure.

Has GM Faced Lawsuits Over the Alleged Fuel Pump Defect?

GM has faced legal action from consumers claiming that the automotive company failed to design a functional engine and resulted in failure.

A GM class action filed in August 2019 claims that the defective fuel pump can “send thousands of metal shards into the fuel injection system and every part of the engine.” Other lawsuits have been filed in Texas, Michigan, Florida, and other courts, reports Autoblog.com.

In July 2019, U.S. District Judge John Tigar rejected a motion filed by GM to dismiss a class action lawsuit over the Duramax fuel pump, according to Reuters.

In addition to claims against GM, consumers have filed claims against other automotive companies and manufacturers who may have made the products or equipped them in their vehicles. Law firms have reportedly filed lawsuits against FCA US LLC, FCA North America Holdings, LLC, F/K/A Chrysler Group, Fiat Chrysler Automobiles, N.V., Ford Motor Company, General Motors LLC, Robert Bosch GmbH, Robert Bosch LLC, VM North America, Inc., and VM Motori S.P.A.

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)

Learn More