Fleece Performance CP3 Conversion Kit with CP3 Pump (FPE-LML-CP3-WP)

This kit takes out the LML's factory CP4 high-pressure fuel pump and puts in the older Bosch CP3 pump instead, with an adapter, preformed fuel hoses, high-flow fittings, a dosing injector distribution block and a wiring extension so everything bolts up.

why this one — A lift pump lowers the odds the CP4 fails. This eliminates the CP4 entirely. The CP3 is the pump Duramax used before 2011 and it does not have the CP4's habit of grenading itself and filling the fuel system with metal, so this is the permanent fix rather than a mitigation. Two things make it worth the money over a bare pump swap: it carries CARB EO D-834-1 so it stays 50-state legal, and Fleece states no tuning is required to run it. It is expensive and it is a full day under the hood, so it makes the most sense on a truck you plan to keep.