Komatsu DNH020_6M_SC(S/N 60001-UP (D20S-6))
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu DNH020-6M-SC (S/N 60001-UP, D20S-6) is a small crawler bulldozer designed for light to medium earthmoving, grading, and site preparation. It belongs to the D20 series lineage, succeeding the D20S-5 and preceding later D20S-7 variants. Operating weights typically range from 8 to 10 tonnes depending on the specific configuration and attachment package. The machine is equipped with a compact diesel engine optimized for fuel efficiency and low ground pressure, making it suitable for confined job sites and residential construction. Configurations include standard and low-ground-pressure (LGP) undercarriage options, various blade types, and ripper attachments.
Across the D20 series generations, Komatsu refined powertrain efficiency, emissions compliance, and operator ergonomics. The DNH020-6M-SC represents a specific serial range within the sixth-generation D20S platform, characterized by updated hydraulic systems and Tier 4 compliant engines. In the used and parts market, this machine remains relevant due to its widespread deployment in municipal and agricultural sectors. Its compact size and proven durability make it a common target for undercarriage replacement, engine overhaul, and hydraulic component sourcing, ensuring a steady supply of aftermarket and genuine parts.
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.
Komatsu DNH020_6M_SC(S/N 60001-UP (D20S-6)) specifications
Engine
| Model | SAA6D107E-1N |
| Type | 4-cycle, water-cooled, direct injection |
| Aspiration | Turbocharged, air-to-air charge air cooler |
| Number of cylinders | 6 |
| Bore x stroke | 110 x 125 mm (4.33 x 4.92 in) |
| Displacement | 5.70 L (347.8 cu in) |
| Horsepower SAE J1995 (Gross) | 168 hp @ 2,200 rpm |
| Horsepower ISO 9249/SAE J1349 (Net) | 158 hp @ 2,200 rpm |
| Rated rpm | 2,200 rpm |
| Fan drive type | Hydraulic |
| Lubrication system | Gear pump, force lubrication |
| Filter | Full-flow |
Weights
| Operating weight (including rated capacity of lubricant, coolant, full fuel tank, operator, and 710 mm (28 in) shoe, less front and rear attachments) | 19,842 lb (9,000 kg) |
Dimensions
| Transport length | 6,630 mm (21 ft 11 in) |
| Transport width | 2,590 mm (8 ft 6 in) |
| Transport height | 3,030 mm (9 ft 11 in) |
| Track gauge | 1,590 mm (5 ft 3 in) |
| Shoe width (standard) | 710 mm (28 in) |
| Ground clearance | 430 mm (1 ft 5 in) |
| Ground contact area | 4,130 cm² (640 in²) |
| Ground pressure (tractor) | 0.75 kg/cm² (10.7 psi) |
Performance
| Travel speed 1st Gear (Forward / Reverse) | 3.4 km/h (2.1 mph) / 3.4 km/h (2.1 mph) |
| Travel speed 2nd Gear (Forward / Reverse) | 5.8 km/h (3.6 mph) / 5.8 km/h (3.6 mph) |
| Travel speed 3rd Gear (Forward / Reverse) | 9.8 km/h (6.1 mph) / 9.8 km/h (6.1 mph) |
| Steering system | Single lever, planetary, wet multi-disc |
| Minimum turning radius | 3,800 mm (12 ft 6 in) |
Blades
| Blade type (standard) | Semi-U (SU) |
| Blade capacity (SU) | 3.50 m³ (4.58 yd³) |
| Blade width | 3,300 mm (10 ft 10 in) |
Service capacities
| Fuel Tank | 210 L (55.5 gal) |
| Engine Oil | 12.0 L (3.2 gal) |
| Cooling System | 14.0 L (3.7 gal) |
| Transmission Oil | 14.0 L (3.7 gal) |
| Final Drives (each side) | 2.3 L (0.6 gal) |
| Hydraulic System | 10.0 L (2.6 gal) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
Komatsu DNH020_6M_SC(S/N 60001-UP (D20S-6)) maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
Servicing the DNH020_6M_SC(S/N 60001-UP (D20S-6)) beyond the schedule
Predictive Maintenance & Fluid Analysis
Utilize KOWA fluid analysis at every 500-hour interval to monitor engine wear metals and hydraulic contamination. Check coolant SCA concentration at 500 hours to prevent liner cavitation. Monitor transmission and final drive oil levels at 250 hours to detect early seal failures. Track fuel filter water accumulation daily to protect the injection system. Use KOMTRAX telematics to correlate load frequency with fluid degradation rates for optimized change intervals.
Corrective & Common Repairs
Address frequent undercarriage wear by measuring sprocket, idler, and roller dimensions at 1,000 hours. Replace hydraulic return filters at 500 hours to prevent valve spool contamination. Inspect and torque cutting edge and end bit bolts at every 500-hour service to maintain blade integrity. Check belt tension and hose clamps at 250 hours to avoid coolant leaks. Replace air filter elements when the restriction indicator signals, prioritizing dusty environments.
Overhaul & Rebuild Points
Plan major powertrain overhaul at 2,000 hours with hydraulic oil changes and transmission service. Inspect turbocharger condition at 1,000 hours for shaft play or oil leaks. Evaluate final drive gear wear during the 1,000-hour oil change. Check structural welds on the blade and ripper frame at 1,000 hours for fatigue cracks. Monitor engine compression and valve clearances during major service intervals to determine optimal rebuild timing.
Seasonal & Environment Servicing
In cold climates, verify coolant freeze protection and use appropriate viscosity engine oil during startup. Clear debris from the radiator and oil cooler fins daily to prevent overheating in dusty conditions. Inspect track tension weekly to adjust for mud or snow accumulation. Check battery terminals for corrosion in humid or coastal environments. Drain the fuel water separator more frequently in wet conditions to prevent microbial growth and injector damage.
DNH020_6M_SC(S/N 60001-UP (D20S-6)) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 103-60-23240 | Cartridge,Hydraulic Oil Filter | Hydraulic service | Check fitment → |
| 113-60-43320 | Cartridge,Hydraulic Oil Filter (D31s) | Hydraulic service | Check fitment → |
| 113-60-43321 | Cartridge,Hydraulic Oil Filter (D31s) | Hydraulic service | Check fitment → |
| 07002-03334 | O-Ring, At Transmission Filter | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
DNH020_6M_SC(S/N 60001-UP (D20S-6)) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| CA115 | Engine crankshaft speed sensor failure | Broken sensor, wiring issue, or connector corrosion | Replace the speed sensor and verify voltage at the pin connector |
| CA441 | Battery voltage too low | Weak battery or charging system failure | Replace the battery or alternator and check the voltage regulator |
| CA442 | Battery voltage too high | Faulty voltage regulator or alternator | Replace the alternator or battery and check the voltage regulator |
| CA122 | Intake air pressure sensor feedback voltage too high | Sensor malfunction or wiring issue | Verify the intake pressure sensor and wiring |
| CA123 | Intake air pressure sensor feedback voltage too low | Sensor short or airflow restriction | Check for a sensor short or an airflow restriction |
| CA153 | Intake air temperature sensor feedback voltage too high | Sensor malfunction | Replace or test the IAT sensor |
| CA154 | Intake air temperature sensor feedback voltage too low | Sensor malfunction | Replace or test the IAT sensor |
| CA451 | Common rail pressure sensor feedback value too high | Fuel rail sensor malfunction or actual overpressure | Diagnose the fuel rail pressure sensor or pump lines |
| CA452 | Common rail pressure sensor feedback value too low | Fuel rail sensor malfunction or low pressure | Diagnose the fuel rail pressure sensor or pump lines |
| CA234 | Engine overspeed | Throttle calibration issue, engine load cycle problem, or operator misuse | Verify throttle calibration, engine load cycle, or operator misuse |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
DNH020_6M_SC(S/N 60001-UP (D20S-6)) attachments & work tools
Blades
The DNH020-6M-SC (D20S-6) is a small bulldozer configuration; specific blade types (S/SU/A) and VPAT availability are not documented in the provided source text for this exact serial range, though the D20S-6 model family is listed in the Komatsu Japan Parts Catalog. Typical widths and capacities for this class vary by configuration/series and are not specified in the source.
Rippers
The source text lists the DNH020-6M-SC (D20S-6) in the Komatsu Japan Parts Catalog but does not provide specific ripper options (multi-shank vs. single-shank) or weights for this model. Ripper data is only explicitly linked to larger models like the D39E-1 and D39P-1 in the aftermarket listings.
Winches
No winch class or towing winch options are documented for the DNH020-6M-SC (D20S-6) in the provided source text. The text mentions winches as a general attachment category for Komatsu bulldozers but provides no model-specific data for this small dozer.
Drawbars/Counterweights
Drawbar and counterweight specifications for the DNH020-6M-SC (D20S-6) are not provided in the source text. The text lists the model in parts catalogs but does not detail attachment compatibility or weights for this specific configuration.
Cab/ROPS Guarding
Forestry or waste configuration guarding options for the DNH020-6M-SC (D20S-6) are not documented in the provided source text. The text references general Komatsu bulldozer features like ROPS but does not specify guarding options for this small model.
Hydraulic Arrangement
Specific hydraulic arrangement notes for front/rear tools on the DNH020-6M-SC (D20S-6) are not included in the source text. The text lists the model in parts catalogs but does not provide hydraulic system details or tool connection specifications.
All DNH020_6M_SC(S/N 60001-UP (D20S-6)) assemblies by section
Every catalogued assembly group for the Komatsu DNH020_6M_SC(S/N 60001-UP (D20S-6)). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Guard
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch)(#60001-60257)
| 01***20 | Bolt,(With Auto Emergency Steering) | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch)(#60258-)
| 01***20 | Bolt,(With Auto Emergency Steering) | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***40 | Bolt,(With Service Valve R.H.) | 4 |
Work Equipment
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment : 3-Point Hitch (1/2)
| 01***45 | Bolt, Mount Center Hinge Retainer (Lower) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
| 01***40 | Bolt (Op) | 8 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment : 3-Point Hitch (2/2)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***25 | Bolt,Without Revolution Sensor | 6 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment : 3-Point Hitch Cylinder
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 2 |
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment : Swing Drawbar (For 3-Point Hitch)
| 01***35 | Bolt,R.H. Outside And L.H. Inside | 8 |
| 01***40 | Bolt,R.H. Outside And L.H. Inside, Bolt | 4 |
| 01***42 | Washer,Spring (For Pedal Steering), Washer-Spring | 12 |
Work Equipment Control System
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : Hydraulic Piping (Valve To Cylinder) (For 3-Point Hitch)
| 01***18 | Bolt | 1 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 1 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : Hydraulic Tank And Filter (For 3-Point Hitch)
| 01***25 | Bolt,Without Revolution Sensor | 7 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 3 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 7 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : P.T.O. Control Lever (For 3-Point Hitch)
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : Work Equipment Control Lever (1/2) (For 3-Point Hitch)
| 01***16 | Bolt (With Air Heater & Conditioner) | 2 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 8 |
| 01***30 | Bolt,(For Mechanical Governor) | 1 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : Work Equipment Control Lever (2/2) (For 3-Point Hitch)
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***05 | Nut,L.H. (For Trimming Dozer) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : Work Equipment Control Valve (1/2) (For 3-Point Hitch)
| 01***16 | Bolt (Op) | 4 |
| 01***25 | Bolt, Seal Cover Mounting | 4 |
| 01***30 | Bolt | 4 |
Komatsu : Dnh020_6m_sc(S/N 60001-Up (D20s-6)) : Work Equipment Control System : Work Equipment Control Valve (2/2) (For 3-Point Hitch)
| 01***08 | Nut (Op) | 1 |
| 07***11 | O-Ring (Kit) | 1 |
| 07***15 | O-Ring,(Without Boom Kickout) | 1 |
DNH020_6M_SC(S/N 60001-UP (D20S-6)) serial number reference
The PIN plate for the Komatsu DNH020-6M-SC bulldozer is located on the front frame casting, typically on the operator's left side near the radiator support. Read the prefix by identifying the code in parentheses following the serial number range (e.g., D20S-6), which indicates the specific model generation and configuration code.
| Prefix | Identifies | Notes |
|---|---|---|
| D20S-6 | DNH020-6M-SC | S/N 60001-UP. Identified in parts catalog listings as the specific model variant for this serial range. The 'D20S-6' code corresponds to the machine model designation within the DNH020 family. No specific engine, steering, or configuration details (Std/XL/LGP) are explicitly tied to this prefix in the provided source text beyond the model code itself. Confirm with dealer for specific configuration mapping. |
Frequently asked questions
What engine does the DNH020-6M-SC use?
The DNH020-6M-SC (S/N 60001-UP) is part of the D20S-6 series. Specific engine model designation and displacement details are not explicitly documented in the provided source text for this exact serial range; verify with your dealer or the machine's data plate.
What is the operating weight of the DNH020-6M-SC?
Operating weights for Komatsu small dozers in this class range from 8 to 10 tonnes (approximately 17,637 to 22,046 lbs), varying by configuration, undercarriage type, and attachment package. Specific weight for this serial range is not explicitly documented in the provided sources.
What model replaced the DNH020-6M-SC?
The DNH020-6M-SC belongs to the D20S-6 series. Successors in the D20S lineage include the D20S-7 series. Specific replacement model designation for this exact serial range is not explicitly documented in the provided sources.
What DNH020_6M_SC(S/N 60001-UP (D20S-6)) owners discuss
What engine powers the Komatsu DNH020_6M_SC(S/N 60001-UP (D20S-6)) bulldozer?
What are the typical hydraulic behaviors and common failure points for this series?
What undercarriage or wear patterns are typical for this machine type?
What are the known engine quirks per series?
What are the common electrical or sensor issues?
What specific fluid specifications should be used for this machine?
What is the critical item to check when buying a used DNH020_6M_SC(S/N 60001-UP (D20S-6))?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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