Doosan DH420 Travel Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy for Excavator Parts

This matched secondary planetary carrier and sun gear unit serves as the core intermediate deceleration component inside the travel final drive, exclusively engineered for Doosan DH420 large heavy-duty crawler excavators. Widely deployed in open-pit mining, large-volume earthmoving, highway subgrade construction and river dredging projects, the DH420 bears extreme continuous heavy loads, steep gradient climbing resistance and frequent rock impact abrasion throughout daily shifts.

The second planetary stage undertakes critical torque conversion after primary deceleration. Once the carrier spider arms crack, sun gear tooth surfaces pit or internal splines suffer severe abrasion, the machine will display noticeable left-right track speed discrepancy, weak walking traction, persistent harsh metal screeching noise and rapid overheating of the entire travel motor housing.

We strictly replie original Doosan factory blueprint data for gear tooth profiles, inner spline parameters and mounting hole layout. This assembly supports direct plug-and-field replacement without secondary drilling, reaming or cutting operations, drastically cutting equipment maintenance downtime. It perfectly addresses the points of long lead times and inflated procurement costs for genuine OEM spare parts, ering to global fleets of used DH420 machines distributed across Africa, Southeast Asia and Central Asia mining zones.

1. 1:1 OEM Precision Matching Customized for Doosan DH420 Travel Final Drive Internal Cavity

   This planetary carrier and sun gear combination is precisely molded to fit the internal structural size of DH420 travel reducers, with zero cross-model compatibility for other Doosan heavy excavators such as DH370 or DX420. Accurate repliion of original spline and gear meshing clearances eliminates track deflection, unstable jitter during walking, harsh internal friction noise and premature abrasion of matched transmission accessories post-installation.

2. Integrated Thickened Forged Body Boosts Long-Term Mining Working Durability

   Most low-cost generic aftermarket planetary carriers easily suffer spider arm fracture or sun gear tooth collapse under round-the-clock continuous heavy mining loads. Our one-piece thick die forging technology paired with complete multi-stage constant-temperature heat treatment significantly elevates the product’s anti-impact and anti-fatigue performance. It maintains stable torque transmission during non-stop large-scale excavation and long-distance cross-region equipment transfer for leasing and pre-owned heavy machine fleets.

3. Two Independent Pre-Delivery Quality Screening Mechanisms Eliminate On-Site Shutdown Losses

   Each finished assembly undergoes two fully independent closed-loop inspection workflows before leaving the factory. Full-range dimension calibration accurately verifies all matching tolerances of gear surfaces and internal splines. Simulated large open-pit mine heavy torque aging test reproduces extreme harsh actual working loads to validate long-term transmission stability. All unqualified semi-finished products are filtered out internally, helping repair service shops and mine operators avoid economic losses caused by unplanned construction halts.

4. High Cost-Performance OEM-Grade Repair Solution for Large Excavator Fleet Operators

   Genuine original Doosan planetary drive spare parts carry extremely high procurement costs and unstable supply cycles for the DH420 classic heavy excavator model widely circulated overseas. Our aftermarket assembly delivers load-bearing capacity and service lifespan equivalent to OEM standards at factory-direct wholesale prices, effectively cutting annual maintenance expenditure for enterprises managing multiple DH420 heavy machine assets.

5. Diversified Global Logistics Channels for International Construction Machinery Spare Parts Wholesalers

   All spot stock goods can be arranged for shipment within 3 working days after payment confirmation. Air freight channels er to urgent emergency breakdown orders from remote mountain mining zones. Consolidated bulk sea freight and full-container FCL shipping provide economical bulk procurement plans for dealers covering Africa, Southeast Asia, Middle East, Central Asia and Latin American markets, with major delivery ports including Guangzhou, Ningbo and Shanghai.

Our production facility specializes in R&D and mass production of planetary transmission spare parts for Korean brand excavators (Doosan & Hyundai) for over 12 years, with travel gearbox planetary carrier assemblies as our core flagship product series. 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 evaluation. Custom heavy-torque test benches replie harsh large mine and highway construction environments to continuously optimize product shock resistance and extend service life. Our planetary transmission spare parts are exported to more than 45 countries and regions worldwide, establishing long-term stable strategic cooperative partnerships with heavy machinery spare parts wholesalers globally.