20Y-27-21140 Final Drive Planetary Carrier for Komatsu Excavator PC200-6

20Y-27-21140 Final Drive Planetary Carrier

The 20Y-27-21140 planetary carrier is a structural and torque-transmitting component used inside the excavator final drive reduction system. It supports the planet gears and keeps them correctly positioned as the gear set rotates under travel load.

Unlike an individual gear, the carrier must control the position of several rotating components at the same time. Wear or deformation in the carrier can therefore affect the entire planetary gear set even when the individual gear teeth still appear usable.

For final drive repairs, the condition of the carrier body, gear support locations and center drive area should be evaluated together rather than checking only the visible gear surfaces.

Why Carrier Alignment Matters

The planet gears rely on the carrier to maintain their working position relative to the other gears in the reduction system. If the carrier support points become worn or distorted, the gears may no longer share the load evenly.

Uneven load distribution can produce localized tooth wear, abnormal backlash and increased mechanical noise. In severe cases, damage that begins at a carrier support area can spread to other parts of the travel gearbox.

A replacement carrier should therefore match the original component not only in overall appearance, but also in its mounting geometry, gear support positions and center drive structure.

Inspect the Original Carrier During Final Drive Repair

When the travel gearbox is disassembled, inspect the carrier carefully for signs that may affect reuse:

• Cracks or deformation in the carrier body

• Oval or worn gear support locations

• Abnormal movement between the gears and carrier supports

• Wear or damage around the center drive area

• Uneven contact marks suggesting poor gear alignment

• Metal debris or heavy contamination inside the reduction gearbox

If one support location shows significantly more wear than the others, the complete planetary stage should be inspected before the gearbox is rebuilt.

One Part Number Across Several Dash-6 Excavators

This carrier appears in several Komatsu Dash-6 excavator applications, but the complete final drive configuration can still vary according to machine series and serial number.

For that reason, matching the excavator model alone should not be treated as the final fitment check. The original component and travel gearbox configuration should also be compared before shipment.

This is particularly useful for older machines that may have received a replacement final drive or rebuilt travel gearbox during previous service.

Information for Carrier Verification

If you need help confirming the correct carrier, send the following information with your inquiry:

• Excavator model and machine serial number

• Final drive or travel gearbox information

• Clear front and side photos of the original carrier

• Overall carrier diameter and height

• Center spline or drive details

• Planet gear and carrier support dimensions when available

Providing these details helps distinguish similar carrier assemblies used in different final drive configurations.

Final Drive Parts Support from Topvelsun

Topvelsun supplies replacement carrier assemblies and other final drive components for excavator repair shops, equipment owners and parts distributors.

Send us part number 20Y-27-21140 together with your machine and original carrier information, and we can help verify the application before quotation.