Excavator Swing Gearboxes
OEM-Spec Replacement for 130+ Machine Models

We supply direct-fit excavator swing gearbox replacements for Caterpillar, Komatsu, Hyundai, Volvo, Hitachi, Doosan, and more — across 6 weight classes from mini excavators to 50t+ heavy machines. Every unit is 100% load-tested before shipment and ships with a signed machinery test report.

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EP 148 4644 Swing Drive Reduction Gearbox 1

What Is an Excavator Swing Gearbox?

An excavator swing gearbox — also called a swing reducer or swing motor drive reduction gear — is the planetary gear unit mounted between the hydraulic swing motor and the machine’s ring gear. Its job: convert high-speed, low-torque motor output into the slow, high-torque rotation that drives the full 360° movement of the upper structure — cab, boom, arm, and bucket — through every dig-and-swing cycle.

When a swing gearbox fails, the excavator cannot rotate its upper body. That grounds the machine completely. Replacement is unavoidable — and fit accuracy matters. Every unit we supply is manufactured to OEM dimensional tolerances for the specific machine model and ships direct-fit, with no shimming or adaptor plates required.

Swing Gearboxes Showcase

How to Identify the Right Swing Gearbox

for Your Machine

Not sure which unit you need? Use this 3-step process before ordering.

Find Your OEM Part Number

Check the original parts manual, your dealer’s parts diagram, or the gearbox casing itself. This is the most reliable reference — send it to us directly.

01

Know Your Machine Model & Serial

Swing gearbox specs can vary by serial number prefix within the same model series. Include both the model (e.g. CAT 320D) and serial prefix when contacting us — this avoids costly ordering errors.

02

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Send Your Requirements

Submit part number, machine model, serial prefix, quantity, and preferred shipping port. We’ll return a confirmed quotation with unit price, freight options, and estimated delivery within 24 business hours.

03

Why OEM Buyers Source Swing Gearboxes From Us

What We OfferThe Specifics
100% Load-TestedEvery swing gearbox runs a no-load run-in then rated-torque bench test before shipment. Signed test report included with every unit.
OEM Dimensional FitManufactured to OEM tolerances for each specific model. Bolt pattern, shaft diameter, port locations — all match factory spec. Average install: 4–6 hours.
No MOQOrder 1 unit for a machine-down emergency or 50 units for fleet stocking. Same lead time. Volume pricing available on request.
4–7 Day In-Stock Lead TimeIn-stock swing gearboxes process in 4–7 business days. Bulk production: 10–35 days depending on quantity. Air freight available for urgent jobs.
3-Month Warranty3 months from arrival date — not our ship date. Defective units replaced. Report with photos and item data; we handle replacement directly.
Full DocumentationSigned test report, video outgoing inspection, commercial invoice, packing list, B/L, and certificate of origin all available. No extra charge.
Flexible ShippingSea (LCL/FCL), air, DHL/FedEx/UPS. EXW, FOB, CFR, CIF. Port: Jiangmen, China. Ships to Canada, Australia, USA, Europe, and 50+ countries.

4 Signs Your Excavator Swing Gearbox

Needs Replacing

Catching these early saves the swing motor from debris contamination — which costs 2–3× more to fix than the gearbox alone.

Jerky or Slow Rotation

Upper body rotates erratically or noticeably slower than normal under load. Often the first symptom operators notice from inside the cab.

Grinding or Whining Noise

Audible grinding, whining, or clicking from the swing motor area during rotation — gear tooth damage or bearing failure is starting.

Metal Particles in Drain Oil

Metal debris in the swing motor case drain oil at routine service. Internal gear wear is accelerating — replacement is now urgent.

Oil Leaking from Housing

Visible oil seepage from the gearbox casing or output shaft seal. A failed seal lets contaminants in and accelerates internal damage rapidly.

Frequently Asked Questions— Excavator Swing Gearbox

Are these aftermarket or genuine OEM swing gearboxes?

Aftermarket, manufactured to OEM dimensional and metallurgical specifications. Not brand-name parts — which is why the price is significantly lower than dealer supply. Every unit must pass our full load test before shipment.

Can I order a swing gearbox replacement for just one unit?

Yes — no minimum order quantity. Machine-down emergency single-unit orders ship on the same processing timeline as bulk. For urgent jobs, choose air freight (5–8 days) at time of order.

How long does it take to install an excavator swing gearbox replacement?

Average field installation: 4–6 hours with standard workshop tooling. All units are direct bolt-on fit — no shimming, no custom adaptor plates, no machine work required. Dimensional drawings available on request before ordering.

My machine model isn't listed. Can you still supply a swing gearbox?

Very likely yes. Send your OEM part number, machine model, and serial prefix. We cover 130+ excavator models. We’ll confirm availability and fit within 4 business hours — no charge for the enquiry.

What should I replace at the same time as the swing gearbox?

When a swing gearbox fails internally, metal debris reaches the hydraulic swing motor case drain within 1–2 operating hours. Flush and inspect the motor; if contamination is confirmed, replacing it simultaneously prevents a second breakdown within 500 hours. We supply both — ask for a combined quote.

Get In Touch

Find Your Excavator Swing Gearbox — Quote in 24 Hours

Tell us your machine model, OEM part number, serial prefix, quantity, and shipping port. We’ll return confirmed price, availability, and freight options within 24 business hours. No minimum order. Ships to Canada, Australia, USA, Europe, and 20+ countries.

24-hour quotation guarantee on all enquiries

MOQ 1 unit — no minimum order quantity required
CE & ISO documentation included with every shipment
OEM / private labelling available on all 10 types
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