2003–2004 5.9L Cummins Injection Pumps & Fuel Supply

Model year 2003 marked the pickup 5.9L Cummins transition to high-pressure common-rail fuel injection. Industrial Injection separates 2003–2004 from the later 2004.5–2007 group because several fuel and air-system applications change at that break.

This collection includes stock and performance CP3 pumps, FCA components, CP3 upgrade parts, rail-pressure components, multiple-pump systems and FASS fuel-supply products. The injection pump creates the high pressure required by the engine's injection system, while a lift or supply pump moves fuel from the tank and feeds the high-pressure side. Upgrading one does not replace the function of the other.

Treat 2003–2004 separately from 2004.5–2007 and verify the exact model year and current fuel or turbo component number. For performance combinations, match pump capacity to injector size, tuning and intended power level rather than choosing a pump only by an advertised flow number.

Related Cummins collections: Engines & Engine Parts, Fuel Injectors & Components, Turbochargers & Turbo Parts.