The 6.7 Cummins engine is one of the most popular and reliable diesel engines used in heavy-duty trucks, agricultural equipment, and industrial machinery. A critical component of its performance is the fuel pump, which ensures proper fuel delivery and efficient combustion. If you are wondering what fuel pump the 6.7 Cummins uses, here’s a clear breakdown.
From its introduction in 2007 until around 2018, most 6.7 Cummins engines were equipped with the Bosch CP3 fuel pump. Known for its reliability and durability, the CP3 pump can handle high fuel pressures, ensuring consistent delivery to the common-rail injection system.
Advantages of CP3:
Proven long-term reliability
Handles high fuel pressure demands
Less prone to catastrophic failure
Starting in 2019, some 6.7 Cummins engines switched to the Bosch CP4 fuel pump to meet updated emissions and efficiency standards. However, the CP4 has been controversial due to higher failure rates compared to the CP3.
Concerns with CP4:
More sensitive to fuel contamination
Higher risk of internal wear and failure
Potential for costly engine repairs if it fails
Due to reliability issues with the CP4, Cummins reintroduced the Bosch CP3 fuel pump in many 2021 and newer 6.7 Cummins applications. This change was welcomed by truck owners who value the CP3’s durability.
The fuel pump plays a critical role in maintaining engine performance. It pressurizes and delivers diesel fuel to the common-rail injectors with precision timing. A failing or weak pump can cause:
Hard starts or no-start conditions
Loss of power and poor acceleration
Excessive smoke from the exhaust
Potential injector and engine damage
Use High-Quality Diesel Fuel: Contaminated or low-quality fuel increases wear.
Change Fuel Filters Regularly: Helps keep debris and water out of the pump.
Consider Lift Pumps: Aftermarket lift pumps can reduce strain on the CP3 or CP4.
Routine Inspections: Keep an eye out for fuel leaks or performance changes.
The type of fuel pump in your 6.7 Cummins depends on the model year:
2007–2018: Bosch CP3
2019–2020: Bosch CP4
2021–present: Bosch CP3 (reintroduced)
For long-term reliability, many owners prefer the CP3 due to its proven performance and lower failure rates. Whether your 6.7 Cummins runs a CP3 or CP4, regular maintenance and proper fuel care are key to keeping your engine running smoothly.