Repower your Cummins 8.9L With our genuine DIESEL PRO Fuel Injector. Replaces Cummins OEM Number 5263319. When replacing a diesel fuel injector its important to identify the original cause of the injector failure. If the original issue is not addressed a repeat failure could occur. Diesel Pro only offers OEM replacement injectors or remanufactured injectors using OE injector components. We pay attention to details during the remanufacturing process and error on the side of caution when replacing components. We only use OEM Nozzles valves and other critical components to ensure product quality and reliability. If you have questions about this product feel free to give us a call