OER Series Duramax 6.6L L5P Fuel Contamination Kit 2017-2020 GM 6.6L Duramax L5P XDP Xtreme Diesel PerformanceThe XDP OER Series Duramax 6. 6L L5P Fuel Contamination Kit XD608 will replace all the debris riddled parts in the fuel system of your 2017 2021 GM 6. 6L Duramax L5P. When the HP4 fuel injection pump fails in your Duramax powered truck, it often sends debris throughout the entire fuel system. This results in contamination from the pump that can contaminate the fuel injector lines, fuel lines, and fuel rails, meaning you now must replace all of these