Komatsubulldozersmall ( - d39)

Komatsu DNH020_6L_LC(S/N 60001-UP (D20PL-6))

Maintenance schedule, common problems & OEM parts breakdown

The Komatsu DNH020-6L-LC (S/N 60001-UP, D20PL-6) is a mid-size crawler bulldozer designed for heavy earthmoving and mining applications. It features a robust undercarriage configuration with an extra bottom roller for extended life and stability. The machine is part of the DNH020 series, which succeeded earlier D20 and D21 model lines, offering a balance of power and maneuverability. Operating weights vary by configuration, typically ranging from 13.8 to 112.62 tonnes across the broader Komatsu dozer lineup, with this specific model falling into the mid-size class. Configurations include standard and low-ground-pressure variants, catering to diverse terrain requirements.

Across generations, the DNH020 series evolved to incorporate advanced Tier 4 emissions technology, improved fuel efficiency, and enhanced operator comfort. The D20PL-6 designation indicates a specific engine and emission package tailored for international markets. In the used and parts market, this machine remains significant due to its durable powertrain and widespread availability of components. The transition to the DNH020 series marked a shift towards higher productivity and lower operating costs, making it a reliable choice for contractors seeking long-term value and proven performance in demanding environments.

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_LC(S/N 60001-UP (D20PL-6)) specifications

Engine

ModelSAA6D107E-1N
Net PowerNot documented for this exact serial range — verify with your dealer
DisplacementNot documented for this exact serial range — verify with your dealer
Emissions TierNot documented for this exact serial range — verify with your dealer

Weights

Operating Weight (Std)Not documented for this exact serial range — verify with your dealer
Operating Weight (XL)Not documented for this exact serial range — verify with your dealer
Operating Weight (LGP)Not documented for this exact serial range — verify with your dealer

Dimensions

Blade Width OptionsNot documented for this exact serial range — verify with your dealer
Transport LengthNot documented for this exact serial range — verify with your dealer
Transport WidthNot documented for this exact serial range — verify with your dealer
Transport HeightNot documented for this exact serial range — verify with your dealer
Track GaugeNot documented for this exact serial range — verify with your dealer
Shoe WidthsNot documented for this exact serial range — verify with your dealer
Ground ClearanceNot 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 PullNot documented for this exact serial range — verify with your dealer
GradeabilityNot documented for this exact serial range — verify with your dealer
Ground Pressure (Std)Not documented for this exact serial range — verify with your dealer
Ground Pressure (LGP)Not documented for this exact serial range — verify with your dealer

Blades

Capacity (S)Not documented for this exact serial range — verify with your dealer
Capacity (SU)Not documented for this exact serial range — verify with your dealer
Capacity (A)Not documented for this exact serial range — verify with your dealer
Capacity (VPAT)Not documented for this exact serial range — verify with your dealer

Service Capacities

Fuel TankNot documented for this exact serial range — verify with your dealer
Hydraulic SystemNot documented for this exact serial range — verify with your dealer
Engine OilNot documented for this exact serial range — verify with your dealer
Cooling SystemNot 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_LC(S/N 60001-UP (D20PL-6)) maintenance schedule

Service intervalTasks
Every 10 h
  • Check engine oil level and condition.
  • Check hydraulic fluid level at sight glass.
  • Check coolant level and ensure cap is secure.
  • Drain water from fuel separator.
  • Check DEF level.
  • Check air filter restriction indicator.
Every 250 h
  • Change engine oil and filter.
  • Grease all points including blade, ripper, and push arms.
  • Check fluid levels.
  • Check air filter outer element.
  • Inspect belts and hoses.
  • Perform visual walk-around inspection.
Every 500 h
  • Replace fuel filter.
  • Replace hydraulic return filter.
  • Perform battery service and load test.
  • Test coolant SCA concentration.
  • Collect KOWA oil sample.
  • Measure undercarriage wear.
Every 1,000 h
  • Collect hydraulic oil sample.
  • Change final drive oil on both sides.
  • Inspect turbocharger.
  • Take wear measurements on critical components.
  • Check valve adjustment.
  • Perform structural inspection.
Every 2,000 h
  • Change hydraulic oil.
  • Flush and replace coolant.
  • Service transmission.
  • Perform comprehensive component evaluation.
  • Check KDPF status.
  • Torque ROPS bolts.

Servicing the DNH020_6L_LC(S/N 60001-UP (D20PL-6)) beyond the schedule

Predictive Maintenance & Fluid Analysis

Utilize KOWA fluid analysis at every 500-hour interval to monitor engine wear metals, hydraulic contamination, and coolant condition. Track ISO cleanliness levels in the hydraulic system to prevent pump and valve failures. Monitor KOMTRAX telematics for load frequency and fuel burn anomalies. Early detection of silicon (dirt) or sodium (coolant) in engine oil prevents catastrophic internal damage. Consistent sampling establishes a baseline for your specific machine's health.

Corrective & Common Repairs

Address undercarriage wear by measuring rollers, sprockets, and idlers at 500-hour intervals. Replace hydraulic return filters promptly to avoid contamination of the main hydraulic system. Inspect turbocharger condition and air filter elements to maintain engine performance. Check final drive oil for metal particles indicating gear wear. Tighten blade and ripper pivot pins to prevent excessive play and structural stress. Replace worn cutting edges and end bits to maintain grading efficiency.

Overhaul & Rebuild Points

Plan major overhauls based on 2,000-hour comprehensive evaluations. Inspect structural welds on the frame and push arms for fatigue cracks. Evaluate the transmission and torque converter for slippage or overheating signs. Check ROPS bolt torque to ensure cab integrity. Assess the condition of hydraulic hoses and clamps for leaks or cracking. Plan for coolant system flush and replacement to prevent corrosion and scaling in the engine block and radiators.

Seasonal & Environment Servicing

In cold climates, ensure coolant concentration is adequate to prevent freezing. Check DEF levels frequently to avoid engine derating. In dusty environments, clean radiator and oil cooler fins daily to prevent overheating. Inspect air filter restriction indicators more often in high-dust conditions. Grease all pivot points more frequently if exposed to abrasive materials. Verify track tension to prevent excessive wear on uneven or rocky terrain.

DNH020_6L_LC(S/N 60001-UP (D20PL-6)) common service parts

Part numberPart
103-60-23240Cartridge,Hydraulic Oil FilterCheck fitment →
113-60-43320Cartridge,Hydraulic Oil Filter (D31s)Check fitment →
113-60-43321Cartridge,Hydraulic Oil Filter (D31s)Check fitment →
07002-03334O-Ring, At Transmission FilterCheck fitment →

Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.

DNH020_6L_LC(S/N 60001-UP (D20PL-6)) fault codes & troubleshooting

CodeMeaningLikely causeWhat to do
CA115Engine crankshaft speed sensor failureBroken sensor, wiring issue, or connector corrosionReplace the speed sensor and verify the voltage at the pin connector
CA111Internal engine controller faultECM hardware failureReplace or reprogram the ECM
CA451Common rail pressure sensor feedback value too highMalfunction in the rail sensor or actual overpressure conditionDiagnose the fuel rail pressure sensor or pump lines
CA441Battery voltage too lowWeak battery or charging system failureReplace the alternator or battery; check the voltage regulator
CA442Battery voltage too highFaulty voltage regulator or alternatorReplace the alternator or battery; check the voltage regulator
CA122Intake air pressure high voltageSensor malfunction or wiring issueVerify the intake pressure sensor and wiring
CA123Intake air pressure low voltageSensor short or airflow restrictionCheck for a sensor short or an airflow restriction
CA153Intake air temperature sensor error (high voltage)Sensor failureReplace or test the IAT sensor
CA154Intake air temperature sensor error (low voltage)Sensor failureReplace or test the IAT sensor
CA234Engine overspeedThrottle calibration error, engine load cycle issue, or operator misuseVerify 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_6L_LC(S/N 60001-UP (D20PL-6)) attachments & work tools

Blades

The DNH020-6L-LC (D20PL-6) is a mid-size dozer compatible with standard, semi-universal, and angle blade configurations. Factory specifications and aftermarket catalogs list blade options for the D20A-6 and D20P-6 series, which share the DNH020 platform, but specific width and capacity metrics for the D20PL-6 variant are not documented in the provided source text. VPAT (Variable Pitch Angle Tilt) blade availability for this specific serial range is not confirmed in the available data. Blade compatibility extends to the D20A-5 and D20A-6 models, indicating standard blade mounting interfaces for this class.

Rippers

Ripper attachments are listed for the D20A-5 and D20P-6 series within the DNH020 family, confirming the availability of rear-mounted ripper options for this machine class. The source text does not specify the shank count (single vs. multi-shank) or the exact weight of the ripper assembly for the DNH020-6L-LC. Ripper components such as cutting edges and shanks are available for the D39P-1 and D41E-6 models, suggesting a modular design approach across the Komatsu mid-size dozer range.

Winches

The provided source text does not contain specific towing winch options, capacities, or mounting details for the Komatsu DNH020-6L-LC. While general bulldozer attachments including winches are mentioned in broader industry contexts, no model-specific winch data is available for the D20PL-6 configuration. Verification with a Komatsu dealer is required to determine if a winch is a factory option or an aftermarket addition for this specific serial range.

Drawbars/Counterweights

Drawbar and counterweight specifications for the DNH020-6L-LC are not detailed in the provided source text. The DNH020 series includes variants with different undercarriage lengths (LC, LT, QC, QT, SC, ST), which may influence counterweight requirements, but specific weights or drawbar configurations for the D20PL-6 are not documented. Compatibility with D20A-5 and D20A-6 components suggests standard structural interfaces, but exact metrics are unavailable.

Cab/ROPS Guarding

Specific forestry or waste configuration guarding options for the DNH020-6L-LC are not listed in the provided source text. The DNH020 series is identified in parts catalogs, but detailed cab protection specifications for specialized applications are not included. General Komatsu dozer lines offer ROPS/FOPS certified cabs, but model-specific guarding details for this serial range require direct dealer consultation.

Hydraulic Arrangement

The DNH020-6L-LC utilizes a hydraulic system compatible with Komatsu Engineering Standard (KES) fluids, including hydraulic oil (HO series) and powertrain oil (TO series). Specific front/rear tool hydraulic arrangement notes for the D20PL-6 are not provided in the source text. The machine shares platform characteristics with the D20A-6 and D20P-6, which may share hydraulic circuit designs, but exact valve configurations for attachments are not documented.

All DNH020_6L_LC(S/N 60001-UP (D20PL-6)) assemblies by section

Every catalogued assembly group for the Komatsu DNH020_6L_LC(S/N 60001-UP (D20PL-6)). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

Guard
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch)(#60001-60558)
01***20Bolt,(With Auto Emergency Steering)3
01***20Bolt,(For Quick Shift) (Mitsubishi)8
01***25Bolt,(For Canvas Canopy?Head Guard)6
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch)(#60559-)
01***20Bolt,(With Auto Emergency Steering)3
01***20Bolt,(For Quick Shift) (Mitsubishi)8
01***40Bolt,(With Service Valve R.H.)4
See all parts with full part numbers in Heavy Parts AI →
Work Equipment
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment : 3-Point Hitch (1/2)
01***45Bolt, Mount Center Hinge Retainer (Lower)4
01***20Bolt,(For Quick Shift) (Mitsubishi)6
01***40Bolt (Op)8
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment : 3-Point Hitch (2/2)
01***16Bolt, Mount Washer Tank To Bracket, Bolt2
01***25Bolt,Without Revolution Sensor6
01***25Bolt,(For Canvas Canopy?Head Guard)4
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment : 3-Point Hitch Cylinder
01***25Bolt,(For Canvas Canopy?Head Guard)2
01***32Washer,(With Auto Emergency Steering)2
07***70O-Ring,(For Intake Air Cover)1
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment : Swing Drawbar (For 3-Point Hitch)
01***35Bolt,R.H. Outside And L.H. Inside8
01***40Bolt,R.H. Outside And L.H. Inside, Bolt4
01***42Washer,Spring (For Pedal Steering), Washer-Spring12
See all parts with full part numbers in Heavy Parts AI →
Work Equipment Control System
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : Hydraulic Piping (Valve To Cylinder) (For 3-Point Hitch)
01***18Bolt1
01***20Bolt,(With Auto Emergency Steering)1
01***20Bolt,(For Quick Shift) (Mitsubishi)2
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : Hydraulic Tank And Filter (For 3-Point Hitch)
01***25Bolt,Without Revolution Sensor7
01***25Bolt,(For Canvas Canopy?Head Guard)3
01***25Washer,Spring?For Additional Rear Lam7
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : P.T.O. Control Lever (For 3-Point Hitch)
01***25Bolt,(Sandy? Dusty Terrain Spec.)2
01***16Bolt, Battery To Frame Ground Wire Attaching2
01***30Bolt,(For Quick Shift) (Mitsubishi)2
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : Work Equipment Control Lever (1/2) (For 3-Point Hitch)
01***16Bolt (With Air Heater & Conditioner)2
01***20Bolt,(With Auto Emergency Steering)8
01***30Bolt,(For Mechanical Governor)1
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : Work Equipment Control Lever (2/2) (For 3-Point Hitch)
01***05Nut,L.H. Thread (D31s)1
01***05Nut,L.H. (For Trimming Dozer)1
01***06Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-108061
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : Work Equipment Valve (1/2) (For 3-Point Hitch)
01***16Bolt (Op)4
01***25Bolt, Seal Cover Mounting4
01***30Bolt4
See all parts with full part numbers in Heavy Parts AI →
Komatsu : Dnh020_6l_lc(S/N 60001-Up (D20pl-6)) : Work Equipment Control System : Work Equipment Valve (2/2) (For 3-Point Hitch)
01***08Nut (Op)1
07***11O-Ring (Kit)1
07***15O-Ring,(Without Boom Kickout)1
See all parts with full part numbers in Heavy Parts AI →

Frequently asked questions

What engine does the Komatsu DNH020-6L-LC use?

The DNH020-6L-LC (S/N 60001-UP, D20PL-6) uses a Komatsu diesel engine configured for Tier 4 emissions compliance. The specific engine model is associated with the D20PL-6 designation, featuring advanced fuel injection and aftertreatment systems for efficiency and emissions control.

What is the operating weight of the Komatsu DNH020-6L-LC?

Operating weight varies by configuration, attachment package, and serial range. Komatsu dozers in this class typically range from 13.8 to 112.62 tonnes across the broader lineup. For the exact weight of the DNH020-6L-LC, consult the specific serial range specification sheet or dealer documentation.

What model replaced the Komatsu DNH020-6L-LC?

The DNH020 series is part of Komatsu's evolving dozer lineup. Successors and related models include the DNH020-6M and DNH031 series, which incorporate updated emissions technology and enhanced features. The specific replacement model depends on the regional market and production year.

What DNH020_6L_LC(S/N 60001-UP (D20PL-6)) owners discuss

What engine powers the Komatsu DNH020_6L_LC(S/N 60001-UP (D20PL-6)) bulldozer?
The machine uses a Yanmar diesel engine. This is confirmed by operator reports noting that all three of their Komatsu D20/D21 series machines utilize Yanmar powerplants, specifically referencing the D21P-5 and D20P-6 variants within the same family. The D20PL-6 designation aligns with this engine family used in the D20/D21 series dozers. Note: Specific Yanmar model codes (e.g., 4TNV98) are not explicitly listed in the provided source text for the D20PL-6 variant, but the engine family is identified as Yanmar. varies by configuration/series
What are the known hydraulic behaviors and common issues for this machine series?
Operators report that Komatsu machines of this era are generally smooth and fuel-efficient. However, a common diagnostic pattern is that if all hydraulic functions become slow, the issue is likely shared (oil level, filters, engine speed) rather than a single pump failure. If only one function is slow, check the specific cylinder, control valve, or pilot input. A specific issue noted for Dash 6 machines (which includes the D20PL-6) is valve problems, particularly on PC150 and PC120 excavators, suggesting potential valve sensitivity in this generation. Also, check for hydraulic oil leaks caused by worn seals or over-pressurized systems. If the machine is weak when hot but works cold, suspect internal leakage in pumps or motors due to viscosity changes.
What undercarriage or wear patterns are typical for the DNH020_6L_LC?
The 'LC' in the model designation indicates a Long Undercarriage configuration with an extra bottom roller installed compared to standard models. Typical wear patterns include degradation of track pads, bushings, and bearings due to environmental factors and usage. Track tension should be monitored regularly as repeated loosening is a common issue. Operators note that components like bushings and bearings are subjected to significant wear and tear, and worn bearings may cause premature failure of the tracks. Check for mud or debris packed into the undercarriage which can cause pulling to one side.
What are the common electrical or sensor issues for this series?
Komatsu machines of this generation rely heavily on electronic control systems. Common issues include intermittent starting, dashboard failure, or random shutdowns triggered by a single faulty sensor or unstable power supply. Owners report that multiple fault codes can appear due to these electrical instabilities. Check battery state of charge, terminals, and engine/chassis grounds. If the machine has a hand priming pump, check the banjo bolt and hose connections for fuel system issues that might mimic electrical faults. Verify sensor functionality and control panel operation.
What is a critical steering issue to check on the D20/D21 series dozers?
On the Dash 5 and similar era Komatsu dozers (including the D20/D21 family), there is a known issue where the inner seal in the steering cylinder was not installed or is prone to failure, with no provision for re-lubrication. This results in 'stickiness' and sometimes eventual freezing of the steering mechanism. Operators should check if the brake crank (forked levers) are free to travel to the unbraked position and verify the adjustment of clutch packs activated by the steering cylinders. Have your dealer verify the steering cylinder seals and clutch pack adjustment.
What fluid specifications are recommended for this machine?
Komatsu recommends using fluids that meet Komatsu Engineering Standards. For hydraulic systems, use Komatsu Hydraulic Oil (HO series) or equivalent ISO VG46/56. For the engine, use Komatsu Diesel Engine Oil (TO series) meeting API CD or higher. For the final drive and axle, use Komatsu Axle Oil (AXO series) meeting API GL-4. For the powertrain/transmission, use Komatsu Powertrain Oil (TO series). For cooling, use Super Coolant AF-NAC. Always verify the exact specification for your specific serial range with the operation and maintenance manual.
What should be checked when buying a used DNH020_6L_LC(S/N 60001-UP (D20PL-6))?
1. Verify the exact serial number and model code to confirm the Yanmar engine type and undercarriage configuration (LC vs standard). 2. Check for hydraulic leaks, especially around cylinders and hoses, and test performance cold vs. hot. 3. Inspect the undercarriage for wear on track pads, bushings, and bearings, and check track tension. 4. Test the steering mechanism for stickiness or freezing, particularly in the steering cylinders. 5. Check the electrical system for intermittent starting, dashboard faults, or multiple fault codes. 6. Inspect the cooling system for blockages between heat exchangers. 7. Verify fuel system integrity, including tank venting, suction lines, and filters. Have your dealer verify the steering cylinder seals and clutch pack adjustment.

Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.

Need a specific DNH020_6L_LC(S/N 60001-UP (D20PL-6)) part?

Search live OEM part data, check fitment, and cross-reference alternatives with Heavy Parts AI.