For more than a decade, dealerships, independent shops, and private truck owners have been dealing with CP4.2 failures. The twin-piston, high-pressure fuel pump employed on the ’11-present 6.7L Power Stroke (as well as the ’11-’16 LML Duramax) has a long history of self-destructing and wrecking the entire fuel system when it lets go. In an instant, the CP4.2, high-pressure lines, fuel rails, and injectors can all become scrap, with a tank cleaning, potential lift pump replacement, and roughly 30 hours of labor all being part of what can easily amount to a $10,000 repair bill. Aftermarket disaster prevention kits and CP3 conversions have become common work-arounds, but only recently has anyone attempted to correct the inherent flaws in the CP4.2’s factory design.
Meet the CP4.2 Bosch should’ve built: the CPX…