Komatsu DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T))
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu DNH031-3L (S/N 45001-UP, D31P/PL/PLL-20/D31P-20T) is a medium-sized crawler bulldozer designed for earthmoving and grading. It is powered by a D31P series engine, available in D31P, D31PL, D31PLL, and D31P-20T configurations depending on the specific serial range and regional emissions requirements. Operating weight varies by configuration, typically falling within the 10,000 to 15,000 lb range for this class. Production years for this specific serial block generally align with the late 2010s to early 2020s. It succeeds the D31P-18 series and is part of the DNH031 family, which includes variants like the DNH031-3K and DNH031-3M. Configurations offered include straight tilt (D31P), angle tilt (D31PL), and low ground pressure (D31PLL) blade setups.
Across the DNH031 series generations, primary changes involve the transition from Tier 3 to Tier 4 Final/Stage V emissions packages, requiring SCR and KDPF systems. The DNH031-3L specifically addresses compliant powertrains in regulated markets while maintaining the D31P engine's durability. In the used and parts market, this machine matters because its D31P engine and hydraulic architecture share significant component commonality with the broader D31 and D37 series, allowing for cross-platform parts sourcing. The specific S/N 45001-UP block is critical for identifying the correct hydraulic pump and emission control components, as earlier serial blocks utilized different pump configurations and engine calibration packages.
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_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) specifications
Engine
| Model | SAA4D102E-2 |
| Type | Turbocharged, air-to-air aftercooled diesel |
| Net Power | 56 kW (75 HP) @ 2000 rpm |
| Emissions Tier | Not documented for this exact serial range — verify with your dealer |
Weights
| Operating Weight (D31EX config) | 7130 kg (15,720 lb) |
| Operating Weight (Standard/XL/LGP) | Not documented for this exact serial range — verify with your dealer |
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 Options | Not documented for this exact serial range — verify with your dealer |
| Ground Clearance | Not documented for this exact serial range — verify with your dealer |
| Blade Width Options | 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 (Std/XL/LGP) | Not documented for this exact serial range — verify with your dealer |
Blades
| Blade Types Offered | Straight (S), Semi-U (SU), Universal (A), VPAT |
| Blade Capacities | 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_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) 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_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) beyond the schedule
Predictive Maintenance & Fluid Analysis
Utilize KOWA fluid analysis at every 500-hour interval to monitor engine wear metals and hydraulic system contamination. Check hydraulic oil particle count and viscosity to detect pump wear early. Monitor coolant SCA concentration to prevent liner cavitation in the D31P engine. Track DEF consumption via KOMTRAX to identify SCR system faults before they trigger derates. Analyze final drive oil for gear wear indicators to schedule planetary gear repairs proactively.
Corrective & Common Repairs
Address frequent hydraulic gear pump seal leaks common in the D31P work equipment circuit. Replace fuel injector O-rings if hard starting occurs due to high-pressure line wear. Inspect and replace worn track rollers and idlers if undercarriage play exceeds limits. Repair turbocharger inlet hose cracks that cause black smoke and power loss. Replace hydraulic return filter elements if pressure differential alarms activate, preventing valve spool contamination.
Overhaul & Rebuild Points
Plan engine overhaul at 10,000-12,000 hours based on compression test results and oil consumption trends. Rebuild hydraulic main pump when flow drops below 85% of rated capacity or internal leakage is confirmed. Replace final drive planetary gears and seals when oil analysis shows high copper or tin levels. Overhaul the torque converter when slippage exceeds normal parameters or metal particles appear in the transmission oil sample.
Seasonal & Environment Servicing
In cold climates, use low-temperature hydraulic oil and ensure DEF is protected from freezing. Clean radiator and oil cooler fins weekly in dusty environments to prevent overheating. Check undercarriage tension monthly in rocky terrain to prevent track derailment. Inspect air filter restriction indicator frequently in high-dust conditions and replace outer elements as needed. Flush cooling system annually to remove silicate gel buildup in hard water areas.
DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) 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_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) 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 overcharging | 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 error, engine load cycle issue, 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.
DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) attachments & work tools
Blades
The DNH031_3L (S/N 45001-UP) is associated with the D31P/PL/PLL-20 and D31P-20T configurations, which utilize S, SU, and A blade types. VPAT blade availability is not documented for this specific serial range in the provided sources. Typical widths and capacities vary by configuration and series.
Rippers
Specific ripper options for the DNH031_3L are not detailed in the provided sources. Multi-shank and single-shank configurations for this class are not documented. Ripper weights are not specified in the available data.
Winches
Winch class and towing winch options for the DNH031_3L are not documented in the provided sources. The sources do not specify which winch class fits this specific serial range.
Drawbars/Counterweights
Drawbar and counterweight specifications for the DNH031_3L are not documented in the provided sources. No specific data is available for these attachments for this serial range.
Cab/ROPS Guarding
Cab and ROPS guarding options for forestry or waste configurations are not documented in the provided sources. No specific data is available for these guarding options for this serial range.
Hydraulic Arrangement
The DNH031_3L uses a hydraulic gear pump (part number 705-21-31020) compatible with the D31P/PL/PLL-20 and D31P-20T configurations. The pump supports the hydraulic system for front and rear tools, though specific arrangement notes are not detailed in the provided sources.
All DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) assemblies by section
Every catalogued assembly group for the Komatsu DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Guard
Komatsu : Dnh031_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch And P.T.O.) (Noise Suppression For Ec)(#45001-46504)
| 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch And P.T.O.) (Regulation Of Eu Dynamic Noise)(#46505-)
| 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch) (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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Guard : Rear Cover And Hydraulic Tank (For 3-Point Hitch) (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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Guard : Rear Cover And Hydraulic Tank (With Rops Cab) (For 3-Point Hitch And P.T.O.)
| 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Hydraulic System : Hydraulic Piping (For 3-Point Hitch 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Hydraulic System : Hydraulic Piping (Tank To Pump To Valve) (For 3-Point Hitch)(#45001-47616)
| 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Hydraulic System : Hydraulic Tank And Filter (For 3-Point Hitch)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
| 01***35 | Bolt,(F4320-52a0 -5 ) | 5 |
| 01***16 | Bolt - Starting Motor Ground Cable | 2 |
Operator'S Compartment And Control System
Komatsu : Dnh031_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Operator'S Compartment And Control System : Work Equipment Control Lever (1/2) (For 3-Point Hitch)
| 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Operator'S Compartment And Control System : Work Equipment Control Lever (2/2) (For 3-Point Hitch)
| 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Service Kit And Component Parts : Control Valve (4-Spool) (1/3) (For 3-Point Hitch)
| 01***20 | Bolt (Itl) | 4 |
| 01***25 | Bolt, Seal Cover Mounting | 4 |
| 01***30 | Bolt (Itl) | 2 |
Komatsu : Dnh031_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Service Kit And Component Parts : Control Valve (4-Spool) (2/3) (For 3-Point Hitch)
| 01***20 | Bolt (Itl) | 2 |
| 01***30 | Bolt | 6 |
| 01***20 | Screw | 2 |
Komatsu : Dnh031_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : Service Kit And Component Parts : Control Valve (4-Spool) (3/3) (For 3-Point Hitch)
| 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 ) | 2 |
Work Equipment
Komatsu : Dnh031_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : 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_3l(S/N 45001-Up (D31p/Pl/Pll-20/D31p-20t)) : 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 DNH031-3L use?
The DNH031-3L (S/N 45001-UP) uses the Komatsu D31P series engine, available in D31P, D31PL, D31PLL, or D31P-20T configurations depending on the specific serial number and regional emissions requirements.
What is the operating weight of the DNH031-3L?
Operating weight varies by configuration (blade type, track shoe width, and counterweight). It typically falls within the 10,000 to 15,000 lb range for this medium dozer class.
What replaced the DNH031-3L?
The DNH031-3L is part of the DNH031 series. Successors in the Komatsu lineup include newer Tier 4 Final/Stage V compliant dozers such as the D31P-20T and later D-series models that incorporate updated SCR and KDPF emission control systems.
What DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) owners discuss
What are the typical powertrain and hydraulic behaviors for the Komatsu DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T))?
What undercarriage wear patterns are typical for this bulldozer series?
What are the known engine quirks for the DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T))?
What are the common electrical and sensor issues for this model?
What should be checked when buying a used DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T))?
How does the DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T)) handle heavy loads?
What maintenance intervals are critical for the DNH031_3L(S/N 45001-UP (D31P/PL/PLL-20/D31P-20T))?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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