Hyundai Excavator Swing Gearbox Replacement: R130, R210 & R290 Guide

Understanding the Hyundai Robex Model Designation

Hyundai’s Robex excavator model numbers use a format of R followed by a number indicating approximate operating weight in tonnes — but this is a rounded approximation, not an exact specification. The R130 is a 13-tonne class machine; the R210 is a 21-tonne class; the R290 is approximately 29 tonnes. Within each class, Hyundai uses a generation letter suffix that changes significantly between production years.

For swing gearbox replacement purposes, the key factors are the specific model generation and the serial number prefix. Hyundai changed the swing gearbox supplier and design between the LC7 and LCR7 generations of the R210, for example — two machines that look identical from the outside but use incompatible swing gearboxes internally. Ordering on model name alone, without the serial prefix, is the most common cause of incorrect replacements in the Hyundai aftermarket.

The generation suffix appears as a number after the model designator. R130LC-9A, R130LC-9S, and R210LC-9 are three different production generations with potentially different swing gearbox part numbers. Always include the complete suffix when requesting a replacement quotation.

Swing Gearbox Variants by Hyundai Model Class

Each Hyundai weight class shares certain physical characteristics that narrow the replacement search before the serial number is confirmed:

The 4 Data Points That Guarantee a Correct Match

Regardless of which Hyundai Robex model class you are working on, these four data points allow a supplier to confirm the correct swing gearbox replacement without ambiguity:

1. Complete machine model including generation suffix: For example, “R210LC-9” not simply “R210.” The suffix identifies the production generation and determines which swing gearbox variant was fitted at the factory.
2. Machine serial number prefix: The first 5–7 characters of the machine serial number identify the production run. Hyundai changed swing gearbox suppliers within the same model generation on several occasions — the serial prefix is the only reliable way to identify which variant is fitted.
3. Existing unit’s part number if accessible: The swing gearbox housing typically carries a stamped or labelled part number. If accessible without full disassembly, this is the most direct confirmation method.
4. Output flange bolt circle diameter and pilot hole diameter: Measure these directly on the existing unit if the part number is not accessible. Two digits — bolt circle PCD and pilot diameter — combined with the model suffix are sufficient for dimensional confirmation in most cases.

Common Cross-Model Compatibility Questions

Can I use an R210 swing gearbox in an R220? In many cases, yes — the R210 and R220 share the same chassis platform in certain generations, and the swing gearbox is dimensionally identical. This must be confirmed by comparing serial prefix ranges, not assumed from model number similarity alone.

Are Hyundai and Samsung excavator swing gearboxes interchangeable? Samsung Heavy Industries supplied certain Hyundai models under OEM arrangements in the LC7 generation period. Some Samsung SE210 and Hyundai R210LC7 swing gearboxes share the same external mounting dimensions. Confirm part number before ordering.

Can I source the swing motor and gearbox together as a combined unit? Yes — combined swing motor and gearbox assemblies are available for most Hyundai Robex models. If your swing motor shows contamination from gearbox debris, requesting a combined assembly from one supplier eliminates the risk of seal interface mismatch and simplifies the repair documentation.

What to Check Before the Replacement Unit Arrives

While waiting for the replacement to ship, two checks on the machine save installation time:

• Inspect the swing motor case drain oil: Collect a sample from the swing motor drain plug. If you find metallic particles or grey silt above the normal level, the motor has likely ingested debris from the failed gearbox. A motor inspection or replacement should be planned concurrently — not deferred to a later service event.
• Clean and inspect the ring gear: Remove any debris from the ring gear teeth that the failed gearbox may have deposited. Check for chipped or spalled teeth on the ring gear — damage here will accelerate wear on the new gearbox output pinion from the first hour of operation.

Browse our full range of excavator swing gearboxes sorted by brand and model, or send your machine model, serial prefix, and quantity to [email protected] for a confirmed part number and quotation within 24 hours.