Komatsu S6D140E-2A-6(S/N 22537-UP)

The Komatsu S6D140E-2A-6 is a 6-cylinder, turbocharged, aftercooled diesel engine belonging to the 6D140-2 family. It is a mechanically governed inline-six designed for heavy-duty applications, primarily powering the Komatsu D275A-5 crawler dozer. The engine features a 140 mm bore and 165 mm stroke, resulting in a displacement of 15.24 L (930 cu in). It is rated in the 306 kW (410 HP) class for the D275A-5 application, though gross power for the 6D140-2 family is published at approximately 368 kW (493 hp) at 1900 rpm. The host machine, the D275A-5, is a roughly 50-tonne class crawler dozer with an operating weight of about 49,850 kg (109,900 lb), depending on blade and undercarriage configuration. This engine was used in the earlier production run of the D275A-5, with later serials moving to the SDA6D140E-3 generation. The predecessor to this dozer line, the D275A-2, utilized a larger-displacement 6D170-family engine. The S6D140E-2A-6 represents a shift toward more compact, higher-boost engines while maintaining comparable power output.

Across the D275A-5's production life, Komatsu transitioned from the SDA6D140E-2E-9 build to the -3 generation without changing the dozer's model designation, eventually introducing the D275A-5R with the larger SAA6D140E-5 engine (about 335 kW / 449 HP) as the current top-of-line machine in this size class. The S6D140E-2A-6 is distinct from the SDA6D140E-2E-9 arrangement, though they share the same base engine family and serial prefix S/N 22537-UP. In the used and parts market, this mechanically governed, pre-electronic engine remains valued for its simplicity and serviceability in remote or extreme-climate operations where diagnostic support is limited. As factory parts supply shifts toward the newer -3 and SAA6D140E-5 generations, demand grows for rebuilt injection pumps, turbochargers, and other take-off components to keep early-serial D275A-5 dozers running. The engine was also offered in a -50C arctic-spec configuration for extreme cold-region operation.

Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.