330C Travel Gearbox 3rd Planetary Carrier Spider With Sun Gear Assy for Excavator Parts 199-4750 7Y-0663 7Y-0639

Cross OEM PN: 199-4750, 7Y-0663, 7Y-0639

This tertiary planetary carrier and matched sun gear assembly serves as the final high-torque output core inside travel final drive, exclusively manufactured for 330C heavy crawler excavators. As a classic heavy-duty machine, 330C is widely applied in open-pit mines, quarries, large earthmoving projects, highway foundation construction and river dredging. It endures long-hour heavy cyclic loads, steep climbing torque and frequent rock impact abrasion during daily operation.

The 3rd planetary stage undertakes the last round of torque amplifiion to drive track movement. Once spider arms crack, sun gear teeth spall or internal splines wear severely, the machine will show uneven track speed, weak walking power, persistent metallic grinding noise and severe overheating of travel motor housing, forcing construction work to stop.

We strictly follow original drawing standards for gear tooth profile, inner spline tolerance and mounting hole layout. The three interchangeable OEM part numbers 199-4750, 7Y-0663, 7Y-0639 support mutual replacement during gearbox overhaul. This assembly is a direct drop-in replacement without cutting, reaming or modifiion on site, greatly shortening maintenance downtime. It effectively solves the points of high prices and long lead times of genuine OEM parts, perfectly matching overseas second-hand 330C fleets in Africa, Southeast Asia and Central Asian mining areas.

1. 1:1 OEM precise matching with three interchangeable part numbers, exclusive for 330C travel final drive The three cross-reference part numbers 199-4750, 7Y-0663, 7Y-0639 can be freely substituted during reducer maintenance. This planetary set is customized to fit the internal cavity of 330C travel gearbox, with no compatibility for other models such as 325C or 330D. Accurate reproduction of original spline and gear meshing clearances eliminates track deviation, unstable walking shake, harsh internal friction noise and premature wear of matching transmission components after installation.
2. Integrated thick one-piece forging greatly extends service life under harsh mining conditions Low-cost generic planetary carriers often suffer broken spider arms or chipped sun gear teeth under round-the-clock heavy mining loads. Our integral thick die forging plus full multi-stage constant-temperature heat treatment significantly improves impact resistance and fatigue resistance. It maintains stable torque transmission during non-stop heavy excavation and long-distance cross-site transfer for rental and used heavy excavator fleets.
3. Two independent pre-delivery quality inspections eliminate costly on-site shutdown losses Every finished assembly goes through two separate closed-loop inspection workflows before leaving the factory. Full-range dimension calibration verifies all matching tolerances of gear surfaces and inner splines. Simulated open-pit heavy torque aging tests replie extreme harsh working conditions to verify long-term transmission stability. All defective semi-finished products are screened out internally, helping repair shops and mine operators avoid economic losses from unplanned machine downtime.
4. High cost-effective OEM-level repair solution for heavy excavator fleet operators Genuine original planetary spare parts have high purchase costs and unstable supply cycles for the widely circulated classic 330C. Our aftermarket assembly achieves the same load capacity and service life as OEM parts at factory direct wholesale prices, effectively cutting annual maintenance costs for enterprises with multiple 330C units.
5. Diversified global logistics solutions for international construction machinery spare parts wholesalers All in-stock products can be shipped within 3 working days after payment confirmation. Air freight meets urgent emergency repair orders from remote mountain mining zones. Consolidated bulk sea cargo and full-container FCL shipping provide cost-saving bulk purchasing plans for dealers covering Africa, Southeast Asia, the Middle East, Central Asia and Latin America.

Our factory specializes in R&D and mass production of excavator final drive planetary transmission spare parts for over 13 years, with travel gearbox planetary carrier assemblies as our flagship product line. We own a complete closed-loop production chain: alloy steel die forging, 5-axis precision gear processing, constant-temperature professional heat treatment and finished product heavy-load simulation testing. Custom heavy-torque test benches simulate harsh mine and highway construction environments to continuously optimize product shock resistance and extend service life. Our planetary spare parts are exported to more than 48 countries worldwide, forming long-term stable strategic cooperation with global heavy machinery spare parts wholesalers.