2413J381 Swing 2nd Planetary Carrier Spider Assembly for Kobelco Excavator SK200-1 SK200-3 SK200LC

2413J381 Swing 2nd Planetary Carrier Spider Assembly

The 2413J381 planetary carrier is used inside the swing reduction gearbox of selected Kobelco excavators. Its enclosed spider-style structure supports the planetary gear set while maintaining the geometry required for torque transmission through the reduction system.

The carrier combines a rigid circular body with multiple planetary support positions around the center drive area. This structure helps keep the gears correctly aligned as the excavator upper structure accelerates, stops and reverses swing direction.

Because the carrier controls the position of several moving components at the same time, dimensional wear or deformation can affect the complete reduction stage even when individual gear teeth still appear serviceable.

Why an Enclosed Carrier Body Matters

The enclosed carrier design provides structural support around the planetary gear positions. Keeping the carrier rigid helps the gears maintain consistent engagement with the surrounding reduction components under changing swing loads.

If the carrier body becomes distorted or one support position develops excessive clearance, gear alignment can change. This may create uneven tooth contact, increased backlash and abnormal noise during swing operation.

A replacement carrier should therefore be checked for overall geometry as well as the visible condition of the planetary gears.

Inspect the Complete Carrier During Gearbox Repair

When the swing reduction gearbox is disassembled, inspect the original carrier for:

• Cracks or deformation in the carrier plates

• Wear around planetary gear support positions

• Excessive movement between the gears and their supports

• Damage or rounding in the center drive area

• Uneven gear contact patterns around the carrier

• Metal particles or abnormal contamination in the gearbox oil

If one planetary position is noticeably more worn than the others, the associated gear, bearing and support surfaces should be checked before the gearbox is reassembled.

Carrier Assembly Configuration Should Be Confirmed

Swing gearbox parts may be supplied as a carrier body, spider assembly or a more complete carrier assembly with internal gears and related hardware already installed.

Before ordering, compare the supplied configuration with the original part and confirm whether you need the carrier structure alone or an assembled gear set.

This is particularly important when repairing older excavators that may have received a replacement or rebuilt swing gearbox during previous service.

Do Not Match a Swing Carrier by Excavator Model Alone

Several carrier assemblies can be used within related Kobelco swing reduction systems. Some may appear similar in photographs while using different carrier bodies, gear layouts, center drive structures or gearbox positions.

The original carrier and swing gearbox information should therefore be compared together rather than selecting a replacement only from the excavator model.

Machine serial information is especially useful when the excavator has a long repair history or the installed swing reducer is not the original factory unit.

Information Needed for Fitment Verification

For a more reliable fitment check, send the following information with your inquiry:

• Excavator model and machine serial number

• Swing reduction gearbox information

• Clear photos of both sides of the original carrier

• Overall carrier diameter and height

• Center drive or spline dimensions

• Planetary gear quantity and support dimensions

These details help distinguish visually similar carrier assemblies used in different swing reduction configurations.

Kobelco Swing Carrier Support from Topvelsun

Topvelsun supplies replacement planetary carriers, spider assemblies and other internal swing reduction components for excavator gearbox repair and parts distribution.

Send us part number 2413J381 together with your machine and original carrier information, and we can help verify the application before quotation.