Komatsu DNH031_3K_E(S/N 42001-UP (D31E-20))
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu DNH031-3K-E (S/N 42001-UP, D31E-20) is a medium-sized crawler bulldozer designed for earthmoving and grading applications. It belongs to the DNH031 series, succeeding the DNH031-3K-D and preceding later DNH031 generations. The machine features a Tier 4 Final / EU Stage V compliant engine, with operating weights typically ranging between 30,000 and 35,000 lbs depending on the blade and counterweight configuration. Configurations include straight tilt dozer variants optimized for fine grading and trimming work. Production years for this specific serial range generally align with the mid-2010s to early 2020s transition period for Komatsu's D31 platform.
Across the DNH031 series, the primary evolution involved emissions compliance upgrades, shifting from earlier D31P/D31S engines to the D31E-20 powertrain in the 3K-E variant. This change necessitated updates to the exhaust aftertreatment system, including KDPF and SCR components, while retaining the robust undercarriage and hydraulic architecture of the D31 lineage. The machine remains significant in the used and parts market due to its balance of power and maneuverability in medium-duty applications. Its widespread use in mining and civil construction ensures a steady demand for D31E-20 specific components, particularly undercarriage wear parts and hydraulic pumps, as owners seek to extend asset life beyond the initial Komatsu CARE warranty period.
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 DNH031_3K_E(S/N 42001-UP (D31E-20)) specifications
Engine
| Model | SAA4D102E-2 |
| Type | Turbocharged and air-to-air aftercooled diesel |
| Net Power | 56 kW (75 HP) @ 2000 rpm |
Weights
| Operating Weight (D31EX) | 7130 kg (15,720 lb) |
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 |
| Track Shoe Width | 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
| Blade Type | Komatsu blade geometry (curvature designed to maximize capacity) |
| Blade Capacity | Not documented for this exact serial range — verify with your dealer |
Service Capacities
| Fuel Tank Capacity | Not documented for this exact serial range — verify with your dealer |
| Hydraulic System Capacity | Not documented for this exact serial range — verify with your dealer |
| Engine Oil Capacity | Not documented for this exact serial range — verify with your dealer |
| Cooling System Capacity | 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 DNH031_3K_E(S/N 42001-UP (D31E-20)) maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
Servicing the DNH031_3K_E(S/N 42001-UP (D31E-20)) beyond the schedule
Predictive Maintenance & Fluid Analysis
Utilize KOWA oil analysis at every 500-hour interval to monitor engine wear metals and hydraulic fluid contamination. Track ISO cleanliness levels in the hydraulic system to prevent pump and valve degradation. Monitor DEF consumption rates via KOMTRAX telematics to identify potential SCR system inefficiencies early. Analyze coolant SCA concentration at 500 hours to ensure proper corrosion inhibition for the D31E-20 engine block. Review fuel filter water separator drainage logs to detect fuel system contamination trends before they impact injector performance.
Corrective & Common Repairs
Address hydraulic gear pump leaks common in the D31E-20 work equipment circuit by inspecting seal integrity during 500-hour services. Replace hydraulic return filters promptly to prevent contamination of the main control valve. Inspect track chain tension and sprocket tooth wear to correct undercarriage misalignment issues. Check turbocharger actuator linkage for free movement to maintain boost pressure. Replace worn blade cutting edges and end bits to reduce drag and improve fuel efficiency during grading operations.
Overhaul & Rebuild Points
Plan engine overhaul around 10,000 hours or when compression tests indicate significant cylinder wear. Inspect final drive planetary gears and axle seals at 5,000-hour intervals for oil leakage or metal particulate in the oil. Evaluate torque converter clutch engagement and stator condition during major transmission service. Check swing machinery bearings and slew ring bolts for wear or loosening. Assess hydraulic cylinder rod scoring and seal condition to determine if rebuild kits are required before catastrophic failure occurs.
Seasonal & Environment Servicing
In cold climates, verify coolant freeze protection levels before winter operations and use low-temperature hydraulic oil if ambient temperatures drop significantly. Clear debris from the radiator and oil cooler fins frequently in dusty environments to prevent overheating. Inspect air filter restriction indicators more often in high-dust conditions and replace outer elements as needed. In wet environments, check undercarriage rollers and idlers for mud packing that can accelerate track wear. Ensure all electrical connections are sealed and dry to prevent corrosion in humid or coastal job sites.
DNH031_3K_E(S/N 42001-UP (D31E-20)) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 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.
DNH031_3K_E(S/N 42001-UP (D31E-20)) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| CA115 | Engine crankshaft speed sensor and backup speed sensor failure | Faulty speed sensor, broken wiring harness, or corroded connector at the pin interface | Replace the speed sensor and verify voltage at the pin connector |
| CA111 | Internal engine controller fault | Electronic Control Module (ECM) internal failure | Replace or reprogram the ECM |
| CA451 | Common rail pressure sensor feedback value too high | Malfunction in the rail pressure sensor or actual overpressure condition | Diagnose the fuel rail pressure sensor or check pump lines |
| CA441 | Battery voltage too low | Weak battery, failing alternator, or loose connections | Replace the alternator or battery; check the voltage regulator |
| CA442 | Battery voltage too high | Failing voltage regulator or alternator overcharging | Replace the alternator or battery; check the voltage regulator |
| AA10NX | Air cleaner clogging | Dirty or blocked air filter element | Replace the air filter |
| CA122 | Intake air pressure sensor feedback voltage too high | Faulty intake pressure sensor or wiring issue | Verify the intake pressure sensor and wiring |
| CA123 | Intake air pressure sensor feedback voltage too low | Sensor short circuit or airflow restriction | Check for a sensor short or an airflow restriction |
| CA153 | Intake air temperature sensor feedback voltage too high | Faulty Intake Air Temperature (IAT) sensor | Replace or test the IAT sensor |
| CA154 | Intake air temperature sensor feedback voltage too low | Faulty Intake Air Temperature (IAT) sensor or short | Replace or test the IAT sensor |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
DNH031_3K_E(S/N 42001-UP (D31E-20)) attachments & work tools
Blades
The DNH031-3K-E (S/N 42001-UP) utilizes the D31E-20 configuration, which is compatible with standard D31-series blade types including Straight (S), Semi-U (SU), and Angle (A) variants, as well as VPAT options where applicable. Typical widths and capacities for this class vary by configuration and series, with specific dimensions not documented in the provided source text.
Rippers
Multi-shank and single-shank ripper options are available for the D31 class, with specific weights and configurations varying by configuration/series. The source text confirms ripper compatibility for the DNH031-3K-E through general D31-series attachment listings but does not provide specific weight data or shank counts for this exact serial range.
Winches
Towing winch options for the DNH031-3K-E are not explicitly detailed in the provided source text, though winches are listed as a general attachment category for the D31 series. Specific class fitment and capacity data for winches on this model are not documented in the sources.
Drawbars/Counterweights
Drawbars and counterweights are available as attachments for the D31 series, with specific fitment for the DNH031-3K-E (D31E-20) configuration not explicitly detailed in the provided text. Availability and specifications vary by configuration/series.
Cab/ROPS Guarding
Forestry and waste configuration guarding options for the DNH031-3K-E are not explicitly detailed in the provided source text. Specific cab or ROPS guarding specifications for this model are not documented in the sources.
Hydraulic Arrangement
The DNH031-3K-E (S/N 42001-UP) is equipped with a hydraulic gear pump (part number 705-21-31020) compatible with the D31E-20 engine configuration. This pump supports front and rear tool hydraulic circuits, though specific flow rates or pressure settings for the DNH031-3K-E are not detailed in the provided text.
All DNH031_3K_E(S/N 42001-UP (D31E-20)) assemblies by section
Every catalogued assembly group for the Komatsu DNH031_3K_E(S/N 42001-UP (D31E-20)). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Guard
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Guard : Rear Cover And Hydraulic Tank (3-Point Hitch? P.T.O. And Ripper) (Noise Suppression For Ec)(#42001-42414)
| 01***25 | Bolt,Without Revolution Sensor | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 20 |
| 01***40 | Bolt,R.H. Outside And L.H. Inside, Bolt | 4 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Guard : Rear Cover And Hydraulic Tank (3-Point Hitch? P.T.O. And Ripper) (Regulation Of Eu Dynamic Noise)(#42415-)
| 01***16 | Bolt (With Air Heater & Conditioner) | 2 |
| 01***25 | Bolt,Without Revolution Sensor | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 20 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch And Ripper) (For 2-Pillar Type Canopy)
| 01***25 | Bolt,Without Revolution Sensor | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 20 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch And Ripper) (For 4-Pillar Type Canopy)
| 01***25 | Bolt,Without Revolution Sensor | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 20 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Guard : Rear Cover And Hydraulic Tank (With Rops Cab) (3-Point Hitch? P.T.O. And Ripper)
| 01***25 | Bolt,Without Revolution Sensor | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 20 |
| 01***40 | Bolt,R.H. Outside And L.H. Inside, Bolt | 4 |
Hydraulic System
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Hydraulic System : Hydraulic Piping (3-Point Hitch Or Ripper Cylinder Line) (Chassis Side)
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 3 |
| 01***09 | Nut,(With Body Positioner) | 4 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 1 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Hydraulic System : Hydraulic Piping (Tank To Pump To Valve) (For 3-Point Hitch Or Ripper)(#42001-42722)
| 01***40 | Bolt,(With Air Conditioner) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Hydraulic System : Hydraulic Tank And Filter (For 3-Point Hitch Or Ripper)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 3 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 3 |
| 01***35 | Bolt,(F4320-52a0 -5 ) | 5 |
Operator'S Compartment And Control System
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Operator'S Compartment And Control System : Work Equipment Control Lever (1/2) (For 3-Point Hitch Or Ripper)
| 01***16 | Bolt - Seat And Tether Belt Mounting | 4 |
| 01***25 | Bolt,(Rear Attachment Less) | 1 |
| 01***30 | Bolt - M8 X 30lg | 3 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Operator'S Compartment And Control System : Work Equipment Control Lever (2/2) (For 3-Point Hitch Or Ripper)
| 01***25 | Bolt,(Rear Attachment Less) | 6 |
| 01***05 | Nut,L.H. (For Trimming Dozer) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
Service Kit And Component Parts
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : 3-Point Hitch Cylinder
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***26 | Nut,Nylon | 1 |
| 01***09 | Nut,(With Body Positioner) | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : Control Valve (4-Spool) (1/3) (For 3-Point Hitch Or Ripper)(#42001-42722)
| 01***20 | Bolt (Itl) | 4 |
| 01***25 | Bolt, Seal Cover Mounting | 4 |
| 01***30 | Bolt (Itl) | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : Control Valve (4-Spool) (1/3) (For 3-Point Hitch Or Ripper)(#42723-)
| 01***12 | Bolt | 4 |
| 01***25 | Screw | 4 |
| 01***30 | Bolt | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : Control Valve (4-Spool) (2/3) (For 3-Point Hitch Or Ripper)(#42001-42722)
| 01***20 | Bolt (Itl) | 2 |
| 01***30 | Bolt | 6 |
| 07***30 | Ring, Seal - Between Sections | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : Control Valve (4-Spool) (2/3) (For 3-Point Hitch Or Ripper)(#42723-)
| 01***12 | Bolt | 2 |
| 01***30 | Screw | 6 |
| 07***38 | O-Ring, (Without Emergency Steering) | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : Control Valve (4-Spool) (3/3) (For 3-Point Hitch Or Ripper)(#42001-42722)
| 07***34 | O-Ring, O-Ring, Oil Level And Fill Plug | 3 |
| 07***34 | O-Ring, At Transmission Filter | 1 |
| 07***34 | O-Ring,(F2310-59a0 -4 ) | 1 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Service Kit And Component Parts : Control Valve (4-Spool) (3/3) (For 3-Point Hitch Or Ripper)(#42723-)
| 07***34 | O-Ring, O-Ring, Oil Level And Fill Plug | 2 |
| 07***34 | O-Ring, At Transmission Filter | 1 |
| 07***34 | O-Ring,(F2310-59a0 -4 ) | 1 |
Work Equipment
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Work Equipment : 3-Point Hitch (1/2)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
| 01***50 | Bolt,(For Tree Pusher) | 10 |
| 01***80 | Bolt,(For 100kg) | 6 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Work Equipment : 3-Point Hitch (2/2)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
| 01***38 | Nut | 2 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 6 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Work Equipment : Drawbar (For 3-Point Hitch)
| 01***55 | Bolt,(With Hook) | 4 |
| 01***12 | Washer,(With Body Positioner) | 1 |
| 01***60 | Flat Washer - M20 (Hardened) | 4 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Work Equipment : Hydraulic Piping (Valve To Cylinder) (For 3-Point Hitch)
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
Komatsu : Dnh031_3k_e(S/N 42001-Up (D31e-20)) : Work Equipment : Swing Drawber (For 3-Point Hitch)
| 01***55 | Bolt,(With Hook) | 10 |
| 01***80 | Bolt,(For 100kg) | 4 |
| 01***60 | Flat Washer - M20 (Hardened) | 14 |
Frequently asked questions
What engine does the DNH031-3K-E use?
The DNH031-3K-E (S/N 42001-UP) uses the D31E-20 engine, which is a Tier 4 Final / EU Stage V compliant powertrain.
What is the operating weight of the DNH031-3K-E?
Operating weight varies by configuration and attachment package, typically ranging between 30,000 and 35,000 lbs.
What model replaced the DNH031-3K-E?
The DNH031-3K-E is part of the DNH031 series lineage; later generations include the DNH031-3L and DNH031-3M variants, which feature updated engine and emissions configurations.
What DNH031_3K_E(S/N 42001-UP (D31E-20)) owners discuss
What engine powers the DNH031_3K_E (S/N 42001-UP / D31E-20)?
What are the common hydraulic behaviors and failure modes for this series?
What undercarriage wear patterns are typical for the DNH031_3K_E?
What are the known electrical and sensor issues for this machine?
What are the typical engine quirks and maintenance needs for the SAA6D107E-2 series?
What should be checked when buying a used DNH031_3K_E (S/N 42001-UP / D31E-20)?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
Need a specific DNH031_3K_E(S/N 42001-UP (D31E-20)) part?
Search live OEM part data, check fitment, and cross-reference alternatives with Heavy Parts AI.