3063955 Final Drive Planetary Gear for HITACHI EX200-3 EX200-5 Excavator

3063955 Planetary Gear for Excavator Travel Reduction Systems

The 3063955 planetary gear is designed for the reduction section of an excavator travel drive. Rather than working alone, the planet gears rotate as a group around the center of the reduction mechanism and share the torque generated during machine travel.

This arrangement allows the final drive to convert motor speed into the high output torque required to move the excavator under load. For this reason, correct gear geometry and consistent contact between the mating surfaces are especially important.

When one planet gear shows abnormal wear, the condition of the complete gear set should be evaluated instead of treating the damaged component as an isolated failure.

Why Planet Gear Matching Matters

Planetary gears operate together under repeated torque loads. Differences in gear profile, bore condition, width or tooth contact can change how the load is distributed across the reduction assembly.

A replacement gear should therefore be compared carefully with the original component. Matching only the outside appearance is not enough, especially when similar travel gearboxes are used across several excavator generations.

If the original gearbox has already experienced heavy wear, checking the mating gears and carrier surfaces before installation can help prevent premature damage to the replacement component.

Wear Patterns Worth Checking

During final drive disassembly, several types of wear can indicate that the planetary gear requires closer inspection:

• Pitting or flaking on the working faces of the gear teeth

• Chipped or rounded tooth edges

• Uneven contact marks across the tooth surface

• Excessive wear or scoring inside the center bore

• Discoloration that may indicate abnormal heat

• Metal debris found in the travel gearbox oil

Heavy wear on more than one surface can indicate a broader alignment, lubrication or bearing problem inside the travel reduction assembly.

Check the Gear Set Before Reassembly

Before rebuilding the final drive, inspect the other planet gears for similar wear patterns and compare their tooth contact surfaces. The carrier pin locations and bearing contact areas should also rotate smoothly without abnormal looseness.

Old oil and metal contamination should be removed from the gearbox before installation. Reusing contaminated lubricant can quickly damage newly installed gear surfaces.

If several gears have developed the same wear pattern, identifying the underlying cause before reassembly is more important than simply replacing the most visibly damaged gear.

Confirm the Original Gear Before Ordering

For machines with multiple travel device configurations, we recommend sending enough information to compare the replacement with the original part. Useful details include:

• Machine model and serial number

• Travel device or final drive identification information

• Clear front and side photos of the original gear

• Outside diameter and center bore diameter

• Overall gear width

• Confirmed tooth count

These details are particularly useful when the machine model has been produced with more than one travel gearbox configuration.

Parts Verification with Topvelsun

Topvelsun can assist repair shops, distributors and equipment owners with travel gearbox component identification before quotation.

Send us part number 3063955 together with your machine and original gear information, and we can help check the application before you place an order.