Caterpillar original For Caterpillar C9 Diesel Common Rail Fuel Injector 573-4231, 577-7633 for Excavator E330D E336D, Replacement for OEM 557-7634, Compatible with 387-9435 original new injector

Precision-engineered as an official Caterpillar fuel system component, the 573-4231 high-pressure common rail injector is purpose-built for Caterpillar C9 ACERT diesel engine platforms, with verified compatibility across industrial, marine, and generator set C9 variants. It is matched to a range of heavy equipment including 950H, 962H, 966H, 972H, and 980H models, as well as excavators, wheel loaders, and stationary power generation units, making it a high-demand part in global heavy equipment and aftermarket supply chains.

Operating within the engine’s high-pressure common rail system, the injector follows ECU commands to deliver precisely metered, atomized fuel directly to the combustion chamber via a multi-hole nozzle. This design supports faster, more complete combustion, improved torque output, better fuel economy, lower particulate emissions, and enhanced engine response, while corrosion-resistant and high-pressure-rated components deliver reliable performance in harsh operating conditions.

Manufactured to strict Caterpillar OEM specifications, the 573-4231 offers extended service life for heavy-duty use cases across construction, mining, marine, and power generation sectors. It shares cross-reference compatibility with multiple OEM and remanufactured part numbers to simplify sourcing for distributors, repair facilities, and equipment operators; engine serial number verification is recommended when using alternative replacement references.