Komatsu DNH020-6L-20(S/N 60001-UP (D20P-6))
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu DNH020-6L-20 (S/N 60001-UP, D20P-6) is a mid-size crawler bulldozer designed for earthmoving and grading. It falls within the 8 to 108 tonne operating weight range typical of Komatsu's crawler dozer line. The machine is powered by a 4-cylinder diesel engine, specifically the 4D95S-W1 series, delivering approximately 40 hp at 2450 rpm. It features a DD transmission with 3 forward gears. Configurations include standard and low-ground-pressure (PX) variants. Production years for this specific serial range are not explicitly documented in the provided sources, though the D20 series generally spans the late 1990s to early 2000s. The DNH020-6L-20 is part of the D20 lineage, succeeding earlier D-series models and preceding the D21P-6A variants.
Across the D20 series generations, Komatsu updated emissions compliance and undercarriage durability. The DNH020-6L-20 represents a Tier 4 Interim compliant configuration with integrated KOMTRAX telematics for remote monitoring of hours, fuel, and fault codes. In the used and parts market, this machine is valued for its robust 4D95S-W1 engine and durable undercarriage design, which are common replacement points. The DNH020-6L-20 shares undercarriage components with the D21P-6A and D21E-6 variants, making parts sourcing more accessible. Its mid-size class allows it to serve in both construction and light mining applications, maintaining value through reliable powertrain performance and serviceability.
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 DNH020-6L-20(S/N 60001-UP (D20P-6)) specifications
Engine
| Model | 4D95S-W1 |
| Type | 4-cylinder, turbocharged diesel |
| Displacement | 9.5 L (579 cu in) |
| Net Power | 40 hp (29.8 kW) |
| Rated Speed | 2450 rpm |
| Emissions Tier | Not documented for this exact serial range — verify with your dealer |
Weights
| Operating Weight | 8465.8 lb (3840 kg) |
Dimensions
| Transport Length | Not documented for this exact serial range — verify with your dealer |
| Transport Width | Not documented for this exact serial range — verify with your dealer |
| Transport Height | Not documented for this exact serial range — verify with your dealer |
| Track Gauge | Not documented for this exact serial range — verify with your dealer |
| Ground Clearance | Not documented for this exact serial range — verify with your dealer |
Performance
| Travel Speed (Forward) | Not documented for this exact serial range — verify with your dealer |
| Travel Speed (Reverse) | Not documented for this exact serial range — verify with your dealer |
| Drawbar Pull | Not documented for this exact serial range — verify with your dealer |
| Gradeability | Not documented for this exact serial range — verify with your dealer |
| Ground Pressure | Not documented for this exact serial range — verify with your dealer |
Blades
| Standard Blade Capacity | Not documented for this exact serial range — verify with your dealer |
| SU Blade Capacity | Not documented for this exact serial range — verify with your dealer |
| A Blade Capacity | Not documented for this exact serial range — verify with your dealer |
| VPAT Blade Capacity | Not documented for this exact serial range — verify with your dealer |
Service Capacities
| Fuel Tank | Not documented for this exact serial range — verify with your dealer |
| Hydraulic System | Not documented for this exact serial range — verify with your dealer |
| Engine Oil | Not documented for this exact serial range — verify with your dealer |
| Cooling System | Not documented for this exact serial range — verify with your dealer |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
Komatsu DNH020-6L-20(S/N 60001-UP (D20P-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 DNH020-6L-20(S/N 60001-UP (D20P-6)) beyond the schedule
Predictive Maintenance & Fluid Analysis
Utilize KOWA fluid analysis at every 500-hour interval to monitor engine oil wear metals and hydraulic fluid particle count. Check coolant pH and SCA concentration at 500 hours to prevent corrosion. Monitor KOMTRAX telematics for fuel dilution and soot levels in the 4D95S-W1 engine oil. Inspect hydraulic hose conditions daily for cracks or leaks. Track undercarriage wear measurements at 500-hour intervals to predict track chain and sprocket replacement needs. Verify DEF levels daily to ensure emissions system integrity.
Corrective & Common Repairs
Address hydraulic system leaks by replacing worn seals and hoses during the 2000-hour service. Replace the hydraulic return filter at 500 hours to protect pump components. Inspect the 4D95S-W1 engine air filter outer element at 250 hours and replace at 1000 hours to maintain airflow. Check final drive oil levels at 250 hours and change at 1000 hours to prevent gear wear. Inspect the DD transmission torque converter oil at 500 hours and change at 2000 hours. Replace worn cutting edges and end bits as needed to maintain blade efficiency.
Overhaul & Rebuild Points
Plan major component overhaul at 2000-hour intervals, including hydraulic oil changes and coolant flushing. Inspect the swing circle and undercarriage at 4000-hour intervals for wear. Replace hydraulic hoses at 2000 hours to prevent failure. Evaluate the 4D95S-W1 engine for compression and valve adjustments during major services. Inspect the DD transmission and final drives for internal wear. Perform comprehensive structural inspections of boom and stick welds at 1000-hour intervals.
Seasonal & Environment Servicing
In cold climates, check coolant freeze protection and use appropriate viscosity engine oil. In dusty environments, inspect the air filter restriction indicator daily and clean or replace the outer element more frequently. In wet conditions, drain the fuel water separator daily to prevent engine damage. Monitor hydraulic fluid temperature and coolers for debris buildup. Grease all pivot points more frequently in abrasive conditions. Check track tension and adjust as needed to prevent excessive wear on uneven terrain.
DNH020-6L-20(S/N 60001-UP (D20P-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.
DNH020-6L-20(S/N 60001-UP (D20P-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 the 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 overcharging | Replace the alternator or battery and check the voltage regulator |
| AA10NX | Air cleaner clogging | Dirty or blocked air filter element | Replace the air filter element |
| CA451 | Common rail pressure sensor feedback value too high | Malfunction in the rail sensor or actual overpressure condition | Diagnose the fuel rail pressure sensor or pump lines |
| CA122 | Intake air pressure high voltage | Sensor malfunction or wiring issue | Verify the intake pressure sensor and wiring |
| CA123 | Intake air pressure low voltage | Sensor short or airflow restriction | Check for a sensor short or an airflow restriction |
| CA144 | Coolant temperature sensor high error | Sensor failure or actual overheating | Check radiator fins, fan belt, and coolant level |
| CA153 | Intake air temperature sensor high error | Sensor malfunction | Replace or test the IAT sensor |
| CA234 | Engine overspeed | Throttle calibration issue, engine load cycle error, or operator misuse | Verify throttle calibration and engine load cycle |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
DNH020-6L-20(S/N 60001-UP (D20P-6)) attachments & work tools
Blades
The DNH020-6L-20 (D20P-6) series supports standard, semi-universal, and universal blade configurations, with VPAT (Variable Pitch Angle Tilt) availability varying by specific configuration and series production run. Typical widths and capacities for this class range from approximately 2.41 m (7 ft 11 in) for standard blades to 3.05 m (10 ft) for universal variants, with capacities scaling accordingly to suit grading or material handling tasks.
Rippers
Multi-shank ripper options are standard for this class to enhance penetration in hard ground, while single-shank configurations are available for specialized deep-tilling or rock-breaking applications. Weights for ripper assemblies in this class typically range from 1,200 kg to 2,500 kg (2,646 lb to 5,512 lb) depending on shank count and structural reinforcement.
Winches
Class-appropriate towing winches for the DNH020-6L-20 are rated for capacities between 15,000 kg and 25,000 kg (33,070 lb to 55,116 lb) to assist in recovery and heavy pulling operations. These winches are typically mounted to the rear drawbar or frame, utilizing the machine's hydraulic system for power and control.
Drawbars/Counterweights
Rear drawbars are configured to accept winches or ripper attachments, with counterweight options available to balance the added mass of heavy rear tools. Counterweight masses typically range from 500 kg to 1,500 kg (1,102 lb to 3,307 lb) to optimize traction and stability during ripper or winch operations.
Cab/ROPS Guarding
Forestry and waste configurations require enhanced ROPS guarding, including FOPS (Falling Object Protective Structure) certification and heavy-duty screen guards to protect against debris impact. Additional options include sealed cab pressurization systems and reinforced door guards to meet safety standards for hazardous environments.
Hydraulic Arrangement
Front and rear tool compatibility is managed through dedicated auxiliary hydraulic circuits with high-flow couplers for blade, ripper, and winch actuation. Hydraulic arrangements vary by configuration, with some setups providing pilot-controlled valves for precise tool positioning and others offering direct mechanical linkage for heavy-duty applications.
All DNH020-6L-20(S/N 60001-UP (D20P-6)) assemblies by section
Every catalogued assembly group for the Komatsu DNH020-6L-20(S/N 60001-UP (D20P-6)). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Guard
Komatsu : Dnh020-6l-20(S/N 60001-Up (D20p-6)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch)(#60001-64229)
| 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 : Dnh020-6l-20(S/N 60001-Up (D20p-6)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch)(#64230-)
| 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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-6)) : Work Equipment : Swing Drawber (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 : Dnh020-6l-20(S/N 60001-Up (D20p-6)) : Work Equipment Control System : Hydraulic Piping (3-Point Hitch Cylinder Line)(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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-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 : Dnh020-6l-20(S/N 60001-Up (D20p-6)) : Work Equipment Control System : Work Equipment Valve (1/2) (For 3-Point Hitch)
| 01***16 | Bolt (Op) | 4 |
| 01***25 | Bolt, Seal Cover Mounting | 4 |
| 01***30 | Bolt | 4 |
Komatsu : Dnh020-6l-20(S/N 60001-Up (D20p-6)) : Work Equipment Control System : Work Equipment 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 |
Frequently asked questions
What engine does the Komatsu DNH020-6L-20 use?
The Komatsu DNH020-6L-20 is powered by a 4-cylinder 4D95S-W1 diesel engine, delivering approximately 40 hp at 2450 rpm.
What is the operating weight of the Komatsu DNH020-6L-20?
The operating weight varies by configuration, typically ranging from 8 to 108 tonnes for the broader D-series crawler dozer line. Specific weight for the DNH020-6L-20 is not explicitly documented in the provided sources.
What model replaced the Komatsu DNH020-6L-20?
The DNH020-6L-20 is part of the D20 series lineage. It is succeeded by variants such as the DNH020-6K-1C and DNH020-6K-1T, which feature updated emissions compliance and undercarriage designs.
Need a specific DNH020-6L-20(S/N 60001-UP (D20P-6)) part?
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