S&S Diesel Motorsports LML-CP3-CARB 50 State CP3 Conversion Kit with Pump CARB Compliant

The S&S Diesel Motorsports LML-CP3-CARB is a CARB-compliant 50-state legal CP3 conversion kit designed for 2011-2016 GM 6.6L Duramax LML engines. This comprehensive solution addresses the notorious CP4.2 high-pressure pump failures that have plagued the LML Duramax platform by replacing the failure-prone CP4 with a proven, durable CP3 high-pressure fuel pump.

Key Features:

• CARB Executive Order #D-756-4 certified for all 50 states
• Includes complete Bosch CP3 pump and all necessary installation hardware
• No tuning or ECM calibration changes required
• Maintains factory emissions control equipment and DPF system
• Drop-in installation with OEM-quality fit and finish
• Prevents catastrophic fuel system failures
• No aftermarket lift pump required for installation
• Backed by manufacturer warranty

The CP4 pump is widely considered the Achilles heel of LML Duramax engines due to high failure rates that can destroy the entire fuel system, including injectors, fuel rails, and lines—resulting in repair costs often exceeding $8,000. This conversion kit proactively eliminates the problem by swapping to the bulletproof CP3 design used in earlier Duramax platforms, providing peace of mind and long-term reliability without sacrificing emissions compliance.