Product Introduction
This comprehensive parts suite encompasses all critical replacement components for the Komatsu HM400 ETT model, covering electrical systems, hydraulic valves, brake assemblies, lubrication parts, fasteners, sensors, wiring harnesses, body components, and cooling system parts. Each item is classified by part number, unit of measure, and recommended quantity for full or partial equipment overhauls, routine preventive maintenance, and emergency field repairs. Unlike generic aftermarket parts, these components undergo rigorous pressure testing (up to 350 bar for hydraulic valves), temperature cycling (-40°C to 120°C), and vibration resistance testing to withstand the harsh demands of off-road mining and drilling operations.
Functional Specifications
- Electrical & Sensor Components: Delivers real-time equipment diagnostics, pressure monitoring, temperature tracking, and safety system activation (emergency steering, hazard signals, brake sensors) with 99.8% signal accuracy; compatible with the HM400’s native ECU system for plug-and-play installation.
- Hydraulic & Brake Parts: Ensures precise fluid control, consistent braking torque, and leak-free operation; solenoid valves and gear pumps maintain optimal hydraulic pressure for load handling and steering functionality.
- Lubrication & Fastening Components: Auto-lubrication systems reduce manual maintenance labor by 40%, while high-strength bolts, washers, and cotter pins resist loosening under extreme vibration and heavy loads.
- Body & Cab Components: Weather seals, grilles, mirrors, and door assemblies enhance operator safety, reduce cabin noise, and protect internal systems from dust, debris, and moisture ingress.
Structural Characteristics
Every component features a robust, application-specific design: critical wear parts use hardened alloy steel for extended durability; seals and gaskets utilize high-grade nitrile rubber for oil and temperature resistance; wiring harnesses feature abrasion-resistant insulation and waterproof connectors; and structural plates/brackets use reinforced steel fabrication to support heavy dynamic loads. All parts are labeled with permanent part number engraving for easy inventory tracking and cross-referencing with Komatsu HM400 ETT service manuals.
Applicable Operating Conditions
These parts are engineered for extreme heavy-duty scenarios including: open-pit mining operations, quarry bulk material transport, construction drilling sites, off-road construction projects, and high-load industrial hauling. They perform reliably in extreme temperatures, high-dust environments, wet and muddy terrain, and continuous heavy-use cycles (12+ hour daily operation). The components are also suitable for scheduled maintenance, mid-life equipment overhauls, and post-failure repair for Komatsu HM400 ETT trucks in fleet and single-unit operations.
Maintenance & Service Recommendations
- Preventive Maintenance Schedule: Inspect sensors, switches, and hydraulic seals every 250 operating hours; replace wear-prone fasteners, washers, and O-rings every 1,000 hours; conduct full lubrication system and brake component inspections every 2,000 hours.
- Installation Best Practices: Use torque-specific tightening for bolts and fasteners (per OEM torque specs) to avoid thread damage; ensure proper sealing for hydraulic and cooling components to prevent leaks; test electrical connections post-installation to verify circuit integrity.
- Storage Guidelines: Store parts in a dry, temperature-controlled environment to prevent corrosion; keep sealed components in original packaging until installation to avoid dust contamination.
- Troubleshooting Tip: Match part numbers precisely to avoid compatibility issues; inspect mating components during replacement to identify secondary wear and prevent repeat failures.
- We supply the following spare parts:
| Short Text | Part Number | UOM |
| AUTO-LUB RS 232 UF008RS LINCOLN | UF008RS | EA |
| DIRECTIONAL SIGNAL UNIT ASSY 569068A960 | 569068A960 | EA |
| HEAD ASSEMBLY 6261717710 KOMATSU | 6261717710 | EA |
| VALVE SOLENOID 56D4337110 KOMATSU | 56D4337110 | EA |
| WASHER 0164330623 KOMATSU | 164330623 | EA |
| PIN,COTTER 0405001612 KOMATSU | 405001612 | EA |
| WASHER 0164330823 KOMATSU | 164330823 | EA |
| BOLT 101080625 KOMATSU | 101080625 | EA |
| BOLT 101080830 KOMATSU | 101080830 | EA |
| PLATE;ASSY,56D5421660,KOMATSU | 56D5421660 | EA |
| LOCK;56B5431640,KOMATSU | 56B5431640 | EA |
| ROD;56B5431620KOMATSU | 56B5431620 | EA |
| PIN;420510622KOMATSU | 420510622 | EA |
| WASHER;164020610KOMATSU | 164020610 | EA |
| NUT;159600606KOMATSU | 159600606 | EA |
| YOKE;1B04316140KOMATSU | 1B04316140 | EA |
| NUT;158010806KOMATSU | 158010806 | EA |
| SENSOR 7861931653 KOMATSU | 7861931653 | EA |
| EVAPORATOR ASSY,ND447610-0630,KOMATSU | ND447610-0630 | EA |
| LOCK;ASSEMBLY,SILVER,4275611790,KOMATSU | 4275611790 | EA |
| DRIVER;LOCK,56B3011530KOMATSU | 56B3011530 | EA |
| WASHER 0164331232 KOMATSU | 164331232 | EA |
| SWITCH, EMERGENCY STEERING 5689511362 KO | 5689511362 | EA |
| SWITCH ASSEMBLY, HAZARD 56D0633851 KOMAT | 56D0633851 | EA |
| SENSOR PRESSURE 7861931620 KOMATSU | 7861931620 | EA |
| SENSOR;7291123000 KOMATSU | 7291123000 | EA |
| SWITCH, PRESSURE;56B4351920KOMATSU | 56B4351920 | EA |
| CONDENSER;AS,56D0731250KOMATSU | 56D0731250 | EA |
| SEAL;O-RING,0700015200 KOMATSU | 700015200 | EA |
| SENSOR;ASSY,7861934930KOMATSU | 7861934930 | EA |
| WASHER 0164331232 KOMATSU | 164331232 | EA |
| WIRING HARNESS 56B0631472 KOMATSU | 56B0631472 | EA |
| GAUGE;AS,56B6113291KOMATSU,HM400 | 56B6113291 | EA |
| STRAINER;705610045 KOMATSU,HM400 | 705610045 | EA |
| PUMP;GEAR,7052225170; BRAKE PUMP_KOMATSU | 7052225170 | EA |
| VALVE ASSEMBLY;1834038000ETT,HM400 | 1834038000ETT | EA |
| PUMP;GEAR,7052225170; BRAKE PUMP_KOMATSU | 7052225170 | EA |
| EVAPORATOR ASSY,ND447610-0630,KOMATSU | ND447610-0630 | EA |
| HARNESS;WIRING,6261816130KOMATSU | 6261816130 | EA |
| CUSHION 4216218550 KOMATSU | 4216218550 | EA |
| CUSHION 4216223710 KOMATSU | 4216223710 | EA |
| BOLT 0101081020 KOMATSU | 101081020 | EA |
| WASHER 0164330623 KOMATSU | 164330623 | EA |
| SEAL 56B5433290 KOMATSU | 56B5433290 | EA |
| BOLT 0101080816 KOMATSU | 101080816 | EA |
| BOLT 0101081040 KOMATSU | 101081040 | EA |
| WASHER 1755434170 KOMATSU | 1755434170 | EA |
| LEVER 17A5445190 KOMATSU | 17A5445190 | EA |
| WASHER 4174316210 KOMATSU | 4174316210 | EA |
| MOTOR ASSEMBLY 4216232700 KOMATSU | 4216232700 | EA |
| GRILLE, L.H 4230752111 KOMATSU | 4230752111 | EA |
| GRILLE, R.H 4230752121 KOMATSU | 4230752121 | EA |
| WASHER 4230941110 KOMATSU | 4230941110 | EA |
| BRAKE PAD 5613461110 KOMATSU | 5613461110 | EA |
| MIRROR, REAR VIEW 561548A612 KOMATSU | 561548A612 | EA |
| SWITCH, EMERGENCY STEERING 5689511362 KO | 5689511362 | EA |
| SENSOR ND4990006160 KOMATSU | ND4990006160 | EA |
| WEATHER STIP 56D5433470 KOMATSU | 56D5433470 | EA |
| WEATHER STIP 56D5433470 KOMATSU | 56D5433470 | EA |
| GLASS 56D5435130 KOMATSU | 56D5435130 | EA |
| SEAL 56D5435170 KOMATSU | 56D5435170 | EA |
| AUXILIARY SEAT 56D5731300 KOMATSU | 56D5731300 | EA |
| WIPER SWITCH 56B0616720 KOMATSU | 56B0616720 | EA |
| PLATE 56B5412331 KOMATSU | 56B5412331 | EA |
| COVER 56B5431991 KOMATSU | 56B5431991 | EA |
| BRACKET 56B5432284 KOMATSU | 56B5432284 | EA |
| COVER 56B5432321 KOMATSU | 56B5432321 | EA |
| COVER 56B5432331 KOMATSU | 56B5432331 | EA |
| STEP 56B5432392 KOMATSU | 56B5432392 | EA |
| PLATE 56B5432430 KOMATSU | 56B5432430 | EA |
| COVER 56B5432581 KOMATSU | 56B5432581 | EA |
| DUCT 56B543A141 KOMATSU | 56B543A141 | EA |
| DUCT 56B543A211 KOMATSU | 56B543A211 | EA |
| COVER 56B543A221 KOMATSU | 56B543A221 | EA |
| FENDER 56B543A321 KOMATSU | 56B543A321 | EA |
| GUARD 56B543A440 KOMATSU | 56B543A440 | EA |
| GUARD 56B543A450 KOMATSU | 56B543A450 | EA |
| SHEET 56B543A740 KOMATSU | 56B543A740 | EA |
| SWITCH ASSEMBLY, HAZARD 56D0633851 KOMAT | 56D0633851 | EA |
| BAR 56D5431B70 KOMATSU | 56D5431B70 | EA |
| MIRROR 56D5432551 KOMATSU | 56D5432551 | EA |
| MIRROR 56D5432551 KOMATSU | 56D5432551 | EA |
| ARM, WIPER 56D5433210 KOMATSU | 56D5433210 | EA |
| DOOR ASSEMBLY 56D5434103 KOMATSU | 56D5434103 | EA |
| COVER;TOP WK LIGHT,56D5438131KOMATSU | 56D5438131 | EA |
| BRACKET;AS,56B5432283KOMATSU | 56B5432283 | EA |
| SEAL;56D5435580KOMATSU | 56D5435580 | EA |
| COVER;DASH PANEL,56D5435510KOMATSU | 56D5435510 | EA |
| TUBE;BRK COOLING,56B6134362KOMATSU | 56B6134362 | EA |
| PIN;COTTER,0405011612KOMATSU | 405011612 | EA |
| BLADE;WIPPER,5695483240KOMATSU | 5695483240 | EA |
| TUBE;R.H CENTER,56B6132850KOMATSU | 56B6132850 | EA |
| SEAL;56D5433960KOMATSU | 56D5433960 | EA |
| BRACKET;AS,56D0636810KOMATSU | 56D0636810 | EA |
| TUBE;R.H. CENTRE,56B6132830KOMATSU | 56B6132830 | EA |
| CLIP, RETAINING;56D5435540KOMATSU | 56D5435540 | EA |
| HARNESS;WARING,6261816120KOMATSU | 6261816120 | EA |
| HARNESS;WIRING,6261816130KOMATSU | 6261816130 | EA |
| TUBE;BRK COOLING,56B6134341KOMATSU | 56B6134341 | EA |
| STEP;56B5437351KOMATSU | 56B5437351 | EA |
| GUARD;56B5437330KOMATSU | 56B5437330 | EA |
| WASHER 0164331232 KOMATSU | 164331232 | EA |
| WIRING HARNESS 56B0631472 KOMATSU | 56B0631472 | EA |
| CLIP 11Y0911140 KOMATSU | 11Y0911140 | EA |
| EVAPORATOR ASSY,ND447610-0630,KOMATSU | ND447610-0630 | EA |
| CAP;1950341390KOMATSU | 1950341390 | EA |
| CAP;17A0342990KOMATSU | 17A0342990 | EA |
| HOSE;2060343331KOMATSU | 2060343331 | EA |
| DIRECTIONAL SIGNAL UNIT ASSY 569068A960 | 569068A960 | EA |
| WIRING HARNESS 56B063A111 KOMATSU | 56B063A111 | EA |
| HARNESS;WARING,6261816120KOMATSU | 6261816120 | EA |
| HARNESS;WIRING,6261816130KOMATSU | 6261816130 | EA |
| HARNESS, WIRING;56B8636540KOMATSU | 56B8636540 | EA |
| HARNESS, WIRING;56B0631223 KOMATSU | 56B0631223 | EA |
| HARNESS, WIRING;56B0633150KOMATSU | 56B0633150 | EA |
| HARNESS, WIRING;56B8636551KOMATSU | 56B8636551 | EA |
| CONDENSER;AS,56D0731250KOMATSU | 56D0731250 | EA |
| HOLDER;5610681520KOMATSU | 5610681520 | EA |
| FUSE;5610681610KOMATSU | 5610681610 | EA |
| SCREW;0102370616KOMATSU | 102370616 | EA |
| HARNESS, WIRING;LOOM,41015239ETT | 41015239ETT | EA |
| SPIDERASSEMBLY 56B2032110 KOMATSU | 56B2032110 | EA |
| SPIDERASSEMBLY 56B2031110 KOMATSU | 56B2031110 | EA |
| WASHER;164332060KOMATSU | 164332060 | EA |
| O RING;07000A5055KOMATSU | 07000A5055 | EA |
| DUSTER;56B2311760KOMATSU | 56B2311760 | EA |
| SHIM;23W2221570KOMATSU | 23W2221570 | EA |
| SHIM;23W2221560KOMATSU | 23W2221560 | EA |
| BOLT;101062050KOMATSU | 101062050 | EA |
| SEAL;701250095KOMATSU | 701250095 | EA |
| CARRIER;56B2731731KOMATSU | 56B2731731 | EA |
| SHIM;23W2221580KOMATSU | 23W2221580 | EA |
| WASHER;4232221240KOMATSU | 4232221240 | EA |
| COVER;56B2711551KOMATSU | 56B2711551 | EA |
| DEFLECTOR;56B2711870KOMATSU | 56B2711870 | EA |
| COVER;56B2739730KOMATSU | 56B2739730 | EA |
| BOLT;101162020KOMATSU | 101162020 | EA |
| COUPLING;56B2731611KOMATSU | 56B2731611 | EA |
| SHAFT;56B203A204KOMATSU,HM400 | 56B203A204 | EA |
| VALVE ASSEMBLY;1834038000ETT,HM400 | 1834038000ETT | EA |
| CUSHION 4216218550 KOMATSU | 4216218550 | EA |
| WASHER 2084371310 KOMATSU | 2084371310 | EA |
| BOLT 01010E1045 KOMATSU | 01010E1045 | EA |
| FILTER ASSEMBLY; 5694383911; KOMATSU | 5694383911 | EA |
| NUT 158211210 KOMATSU | 158211210 | EA |
| BOLT;101911220KOMATSU,HM400 | 101911220 | EA |
| SENSOR, TEMPERATURE (BRAKE 7861923320 KO | 7861923320 | EA |
| VALVE ASSEMBLY 56D4337101 KOMATSU | 56D4337101 | EA |
| PUMP;GEAR,7052225170; BRAKE PUMP_KOMATSU | 7052225170 | EA |
| VALVE;7218912011KOMATSU,HM400 | 7218912011 | EA |
| SEAL;O-RING,0700015200 KOMATSU | 700015200 | EA |
| SENSOR;ASSY,7861934930KOMATSU | 7861934930 | EA |
| SWITCH;4184337681KOMATSU,HM400 | 4184337681 | EA |
| PUMP 21000221 ETT | 21000221 | EA |
| DIAPHRAGM PUMP 202-021–11 ETT | 202-021–11 | EA |
| PUMP 21000221 ETT | 21000221 | EA |
| KPA GUAGE 12500100 ETT | 12500100 | EA |
| KITS, GREASE PALE,450KG 33020968 ETT | 33020968 | EA |
| KITS, GREASE PAIL 1000KG 33021097 ETT | 33021097 | EA |
| P203 STANDARD INSTALLATION KIT LINCOLN | P203 | EA |
| FASTENER, ANTILUCE 20100097 ETT | 20100097 | EA |
| HYDRAULIC DURAMAX HMK05 20152002 ETT | 20152002 | EA |
| PRESSURE WASHER, HYDRAULIC 21000035 ETT | 21000035 | EA |
| LDC-016-B-0 PARKER COOLER 21000109 ETT | 21000109 | EA |
| VALVE, 6 BANK, L90LS, 18692 21000198 ETT | 21000198 | EA |
| GAUGE, LEVEL, TEMP 5″ 21000197 ETT | 21000197 | EA |
| VALVE, GATE, BRASS, 1 1/2″ 40MM 20100094 | 20100094 | EA |
| SWITCH, PNEUMATIC,3/2(GEARBOX) 25000312 | 25000312 | EA |
| VALVE, ROTARY 3 POS, 4 WAY 21000142 ETT | 21000142 | EA |
| PISTON;21500001ETT,HM400 | 21500001 | EA |
| SEAL;1834854802ETT,HM400 | 1834854802 | EA |
| PUMP 21000221 ETT | 21000221 | EA |
| VALVE, ROTARY 3 POS, 4 WAY 21000142 ETT | 21000142 | EA |
| MANIFOLD;951280013ETT,HM400 | 951280013 | EA |
| P203 STANDARD INSTALLATION KIT LINCOLN | P203 | EA |
| S/S 201-219-00=FILTER 20124408 ETT | 20124408 | EA |
On-Site Field Failure Repair Cases (Real-World Scenarios)
Case 1: Hydraulic Solenoid Valve Malfunction
A Komatsu HM400 ETT truck experienced unresponsive steering controls mid-operation in a mining quarry. Diagnosis revealed a faulty 56D4337110 solenoid valve with internal seal degradation. Replacing the OEM solenoid valve restored hydraulic pressure and steering functionality within 90 minutes, eliminating 8+ hours of unplanned downtime.
Case 2: Wiring Harness Short Circuit
A fleet HM400 ETT had intermittent sensor failures and dashboard error codes, traced to a damaged 56B0631472 wiring harness from dust and vibration damage. Installing the OEM wiring harness resolved electrical faults, restored sensor communication, and prevented potential full-system electrical failure.
Case 3: Brake Pump Performance Loss
An HM400 ETT exhibited reduced braking power and delayed response during hauling. Inspection showed worn internal components in the7052225170 gear brake pump. Replacing the OEM pump restored full braking torque and pressure, meeting heavy-duty safety standards and avoiding regulatory violations.
Frequently Asked Questions (FAQ)
| Question | Answer |
| Are these parts compatible only with the Komatsu HM400 ETT model? | Yes, these parts are precision-engineered exclusively for the Komatsu HM400 ETT articulated dump truck to ensure perfect fitment and OEM-level performance; they are not designed for other Komatsu models or non-Komatsu equipment. |
| How do I verify the correct part number for my HM400 ETT repair? | Cross-reference the failed component’s engraved part number with this list, or match the equipment’s serial number to the corresponding OEM service manual for accurate part selection to avoid fitment errors. |
| Do these parts come with OEM-quality certification? | All parts meet Komatsu’s strict OEM manufacturing standards, undergo rigorous quality testing, and are built to the same tolerances as factory-installed components for reliable, long-lasting performance. |
Procurement Guidance & Closing Call to Action
For equipment managers and maintenance teams relying on the Komatsu HM400 ETT for critical hauling and drilling operations, this parts list serves as both a definitive procurement reference and a technical repair guide. Investing in genuine OEM Komatsu ETT parts mitigates the risk of costly downtime, subpar aftermarket performance, and safety hazards, while ensuring your equipment operates at peak efficiency for its full service life. Whether you are conducting routine preventive maintenance, addressing urgent field repairs, or planning a full equipment overhaul, this curated parts selection provides the precision, durability, and compatibility required to keep your HM400 ETT operational in even the harshest working conditions.
