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S&S Diesel CP3 Conversion Kit W/ Re-Calibrate Pump | 2011-2016 Duramax

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Product Information

Catastrophic failure on CP3 fuel injection pumps on 2011-2016 LML Duramax trucks will send small metallic debris throughout the entire fuel system. Our CP3 conversion kit will allow you to replace your less-reliable CP4 fuel injector pump before you experience catastrophic failure. This kit can also be used if you have a failed pump that did not destroy your fuel rails or injectors. For those who did experience complete failure and need to replace the fuel rails and injectors, check out our complete CP4 fuel system replacement kit. 

This CP3 conversion kit includes a new S&S modified CP3 fuel injection pump, fuel lines, and the install kit to get your CP4 converted to a CP3 injector pump. This kit requires no tuning and is EPA approved. The CP3 pump is already re-calibrated to match the LML stock CP4 fuel curve. This kit is designed to replace the less reliable CP4 that comes stock on the LML.


  • No Tuning Required
  • EPA Approved
  • Recalibrated To Match LML Stock CP4 Fuel Curve


  • New S&S Modified CP3
  • Comprehensive Kit
  • Replaces Less Reliable CP4

Kit Includes

  • CARB CP3 Pump
  • Fuel lines
  • Install Kit

Duramax LML CP4 Pump Failure

The CP4 fuel injection pump in 2011-2016 Duramax trucks suffer high pressure fuel pump issues due to lack of lubrication. The CP4 was designed to be a more efficient pump than its predecessor, the CP3 pump. However, the CP4 proved to be less reliable than the CP3. An LML CP4 pump failure will present itself with a hard start or no start condition and can result in the following trouble codes: P0087, P0088, P0191, or P128E. This can be confirmed by removing the CP4 pump and fuel pressure regulator and checking for cracks and metal debris on the fuel pressure regulator screen.

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