2011-2016 GM/CHEVROLET 6.6L DURAMAX FLEECE LML CP3 CONVERSION KIT WITH CP3 PUMP
The Fleece Performance CP3 Conversion Kit with CP3 Pump for the 2011–2016 GM 6.6L LML Duramax is a comprehensive solution engineered to eliminate the well-documented failure risks associated with the factory CP4 high-pressure fuel pump. The LML platform’s CP4 pump is known for internal component failure that can introduce metal debris into the entire fuel system, often resulting in catastrophic damage requiring complete system replacement. This complete conversion kit replaces the CP4 with a proven Bosch CP3 pump, delivering significantly improved durability, fuel delivery consistency, and long-term reliability.
Designed with OEM-level fit and finish, this kit includes a brand-new CP3 pump along with Fleece-exclusive molded fuel lines, high-flow fittings, and a precision-engineered mounting system. The system is designed to integrate seamlessly into the factory fuel architecture without requiring ECM tuning when used with a stock CP3 configuration, making it ideal for both stock and mildly modified trucks. Additionally, the inclusion of a valley feed line supports compatibility with aftermarket lift pumps, further enhancing fuel system efficiency under demanding conditions.
What’s Included
- Brand new Bosch CP3 high-pressure fuel pump
- CP3 mounting adapter plate
- CP3 to rail high-pressure fuel line
- High-flow CP3 feed and return fuel fittings
- Preformed fuel feed and return hoses
- Valley feed fuel line (lift pump compatible)
- FCA (Fuel Control Actuator) extension harness
- Dosing injector feed line / distribution components
- Low-pressure fuel feed line
- Complete installation hardware kit (brackets, bolts, clamps)
Features & Benefits
- Eliminates CP4 failure risk by converting to a more reliable CP3 fuel pump design
- Prevents costly fuel system contamination caused by CP4 internal failure
- Improves fuel delivery stability and consistency under load and towing conditions
- Supports increased horsepower potential compared to factory CP4 limitations
- OEM-style fitment ensures clean installation with factory-like routing and integration
- No tuning required when used with standard CP3 configurations
- High-flow fuel fittings and molded hoses improve fuel system efficiency
- Valley feed design allows seamless integration with aftermarket lift pumps
- Maintains factory emissions equipment compatibility in most configurations
- Proven solution for both daily-driven and performance-oriented Duramax builds
Compatibility / Vehicle Applications
- 2011 Chevrolet Silverado 2500HD 6.6L LML Duramax
- 2011 Chevrolet Silverado 3500HD 6.6L LML Duramax
- 2012 Chevrolet Silverado 2500HD 6.6L LML Duramax
- 2012 Chevrolet Silverado 3500HD 6.6L LML Duramax
- 2013 Chevrolet Silverado 2500HD 6.6L LML Duramax
- 2013 Chevrolet Silverado 3500HD 6.6L LML Duramax
- 2014 Chevrolet Silverado 2500HD 6.6L LML Duramax
- 2014 Chevrolet Silverado 3500HD 6.6L LML Duramax
- 2015 Chevrolet Silverado 2500HD 6.6L LML Duramax
- 2015 Chevrolet Silverado 3500HD 6.6L LML Duramax
- 2016 Chevrolet Silverado 2500HD 6.6L LML Duramax
- 2016 Chevrolet Silverado 3500HD 6.6L LML Duramax
- 2011–2016 GMC Sierra 2500HD / 3500HD 6.6L LML Duramax
The Fleece CP3 conversion kit with pump is widely regarded as one of the most effective reliability upgrades available for the LML Duramax platform, addressing a critical OEM weakness while simultaneously improving fueling capacity and system longevity. Whether the truck is used for heavy towing, fleet work, or performance applications, this conversion provides a long-term solution that dramatically reduces the risk of catastrophic fuel system failure while enhancing overall drivability and confidence.
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California Proposition 65 Warning
WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm.
For more information, go to www.P65Warnings.ca.gov
