Komatsu Gear Crankshaft 6221-31-1120

The Komatsu Gear Crankshaft 6221-31-1120 is identified in the supplied parts catalog as a CRANKSHAFT & RELATED PARTS for specific Komatsu diesel engine and equipment configurations. Cataloged engine models include S6D108-1, SA6D108-1, and SAA6D108E-2A. Listed machine applications include WA320-3-X / 3-XR, WA320-3, WA380-3, WA380-3H, and D57S-1B. Use the complete model and serial-number details below to compare this part with the equipment being serviced.

What is 6221-31-1120 used for?

Part number 6221-31-1120 is cataloged as a Gear Crankshaft. It appears in the CRANKSHAFT & RELATED PARTS parts group. The correct selection depends on the engine model, machine model, and the applicable serial-number range.

Compatible engine models

S6D108-1, SA6D108-1, SAA6D108E-2A

Engine models with serial-number ranges

S6D108-1 (Build 7A) ? 11731-Up | SA6D108-1 (Build 7B) ? 10001-Up | SAA6D108E-2A (Build 7C) ? 19030-Up

Application models without serial numbers

WA320-3-X / 3-XR, WA320-3, WA380-3, WA380-3H, D57S-1B, PC300-5 / 5T / LC-5T, PC300-5K, PC300LC-5K, PC300NLC-5K, PC300HD-5K, PC300LC-5, PC300LC-5, PC360LC-5, WA420-3, WA420-3, WA420-3X / 3X-R, PC300-6, PC300-6Z, PC300LC-6, PC300LC-6Z, PC340LC-6K, PC340NLC-6K, PC350-6, PC350LC-6, PC380LC-6K, PC380LC-6K-J

Applications with serial-number ranges

WA320-3-X / 3-XR S/No. 50001-52999, WA320-3 S/No. 53001-Up, WA380-3 S/No. 50001-Up, WA380-3H S/No. 20051-20500, D57S-1B S/No. 20001-Up, PC300-5 / 5T / LC-5T S/No. 20001-Up, PC300-5K S/No. K20001-Up, PC300LC-5K S/No. K20001-Up, PC300NLC-5K S/No. K20001-Up, PC300HD-5K S/No. 20001-Up, PC300LC-5 S/No. 20001-Up, PC300LC-5 S/No. A20267-A30000, PC360LC-5 S/No. 20001-Up, WA420-3 S/No. 50001-Up, WA420-3 S/No. 53001-Up, WA420-3X / 3X-R S/No. 50001-52999, PC300-6 S/No. 30001-Up, PC300-6Z S/No. 30001-Up, PC300LC-6 S/No. 30001-Up, PC300LC-6Z S/No. 30001-Up, PC340LC-6K S/No. 10001-Up, PC340NLC-6K S/No. 10001-Up, PC350-6 S/No. 10001-Up, PC350LC-6 S/No. 10001-Up, PC380LC-6K S/No. K30001-Up, PC380LC-6K-J S/No. 10001-Up

How do I confirm fitment?

Match 6221-31-1120 to the existing part number and verify the complete engine model, equipment model, and serial number. A shared model name does not confirm compatibility because production changes can affect the required component.

Frequently asked question

Will 6221-31-1120 fit every listed Komatsu machine?
No. Fitment is limited to the cataloged engine, application, and serial-number combinations. Confirm all identifying information before ordering.