Doosan 401107-00578 Arm Cylinder Seal Kit

The Doosan 401107-00578 is a hydraulic cylinder seal kit designed for the arm cylinder of specific Doosan and Daewoo excavator models. It contains all necessary seals, wipers, wear rings, and O-rings required for a complete cylinder rebuild. Manufactured to meet or exceed OEM specifications, the kit utilizes high-grade sealing materials including PTFE, polyurethane (PU), and nitrile rubber (NBR) to withstand high operating pressures, temperature variations, and contaminated hydraulic fluid environments common in construction machinery applications. This kit ensures precise fitment and restores original cylinder performance, preventing internal bypass and external leakage. Compatible with Doosan DX530LC-5, DX520-9C, DX380LCA, DX380LC, and DX340LC excavators. Replaces OEM part number 401107-00578. Direct interchange for aftermarket equivalents supplied by major hydraulic seal distributors.