Komatsuengine(no series)

Komatsu 4D95L-W-1E(S/N 11437-UP)

Maintenance schedule, common problems & OEM parts breakdown

The Komatsu 4D95L-W-1E engine (S/N 11437-UP) is a compact diesel power unit manufactured since 2017 with a 3.3-liter displacement and four cylinders. It delivers 45 to 60 kW (60 to 80 hp) at approximately 2,200 rpm. This engine powers the Komatsu WA70-1 wheel loader series and the PC120 excavator series. Operating weights for these machines range from 6,180 kg (13,624 lb) for the PC60 class to 34,500 kg (76,058 lb) for larger wheel loaders. The 4D95L-W-1E succeeded earlier 4D95L variants and is part of the 95 Series engine family. Configurations include mechanical and common-rail fuel injection options.

Across generations, the 4D95L-W-1E transitioned from mechanical fuel systems to electronic control for improved efficiency and emissions compliance. The S/N 11437-UP break distinguishes it from earlier 4D95L-W-1A and 4D95L-W-1B variants. In the used and parts market, this engine remains critical because it shares components with the Cummins 3.3L platform, allowing for cost-effective aftermarket rebuild kits. Its compact size and reliability in compact excavators and wheel loaders ensure high demand for service manuals, gasket kits, and overhaul 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 4D95L-W-1E(S/N 11437-UP) specifications

Engine

Model4D95L-W-1E
Serial Range11437-UP
Cylinders4
Displacement3.3 L (201 cu in)
Emissions TierNot documented for this exact serial range — verify with your dealer
Gross/Net PowerNot documented for this exact serial range — verify with your dealer

Weights

Operating WeightNot documented for this exact serial range — verify with your dealer
Shipping WeightNot documented for this exact serial range — verify with your dealer
Ground PressureNot documented for this exact serial range — verify with your dealer

Dimensions

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
Ground ClearanceNot documented for this exact serial range — verify with your dealer

Performance

Travel SpeedNot documented for this exact serial range — verify with your dealer
GradeabilityNot documented for this exact serial range — verify with your dealer

Service capacities (summary)

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 4D95L-W-1E(S/N 11437-UP) 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
  • Check fuel level and drain water from separator
  • Check DEF level on Tier 4 machines
  • Check air filter restriction indicator
Every 250 h
  • Change engine oil and filter
  • Grease all points including boom, stick, bucket, and swing bearing
  • 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
  • Service battery and load test
  • Test coolant SCA concentration
  • Collect KOWA oil sample
  • Perform detailed undercarriage inspection
Every 1,000 h
  • Collect hydraulic oil sample
  • Change final drive oil
  • Inspect turbocharger
  • Check valve adjustment
  • Measure wear on components
  • Perform structural inspection of boom and stick
Every 2,000 h
  • Change hydraulic oil
  • Flush and replace coolant
  • Service transmission
  • Perform comprehensive component evaluation
  • Check KDPF status
  • Inspect and replace worn belts and hoses

Servicing the 4D95L-W-1E(S/N 11437-UP) beyond the schedule

Predictive Maintenance & Fluid Analysis

Utilize KOWA fluid analysis at every 500-hour interval to monitor wear metals and contaminants in the 4D95L-W-1E engine. Check coolant SCA concentration at 500 hours to prevent scaling in the 3.3-liter block. Monitor hydraulic oil particle count and viscosity to protect the high-pressure injection system. Track engine oil viscosity and fuel dilution to detect piston ring wear early. Use KOMTRAX telematics to log load frequency and fault codes for proactive scheduling. Inspect air filter restriction indicators daily to maintain airflow for the turbocharger.

Corrective & Common Repairs

Address intermittent starting and dashboard failures by checking the engine controller power supply and sensor wiring on the 4D95L-W-1E. Replace worn fuel injectors if power loss or increased fuel consumption occurs. Fix exhaust leaks in the cooling system by inspecting head gaskets and cylinder sleeves. Replace the water pump if overheating persists. Check the alternator and starter connections for corrosion. Replace the fuel filter and drain the water separator to prevent injector clogging. Inspect the turbocharger for shaft play and oil leaks.

Overhaul & Rebuild Points

Perform an inframe overhaul on the 4D95L-W-1E engine when wear measurements exceed factory limits. Replace pistons, rings, and rod bushings using the specific 4D95L-W-1 series kit. Inspect the crankshaft for scoring and replace main bearings if clearance is excessive. Check the cylinder block for cracks or sleeve leakage. Replace the camshaft and cam bearings if valve timing is off. Rebuild the fuel injection pump and replace nozzle tips. Ensure all gaskets and seals are OEM-spec for the 95 Series engine family.

Seasonal & Environment Servicing

In cold weather, check the coolant glycol content and use Komatsu Super-coolant AF-NAC to prevent freezing in the 4D95L-W-1E block. Inspect the battery for charge retention in low temperatures. In dusty environments, clean the radiator and oil cooler fins daily to prevent overheating. Check the air filter more frequently and replace the outer element as needed. Inspect hydraulic hoses for cracking due to UV exposure. Grease all pivot points on the undercarriage and attachment linkage to remove abrasive dust. Drain water from the fuel separator daily to prevent microbial growth.

4D95L-W-1E(S/N 11437-UP) common service parts

Part numberPart
07281-00197Clamp,(With Pre-Fuel Filter)Check fitment →
600-311-6220Cartridge,Fuel FilterCheck fitment →
600-311-9600Fuel Filter Ass'YCheck fitment →
09637-02161Plate? Instruction,Air Cleaner (Double Element)Check fitment →
09637-01661Plate? Instruction,Air Cleaner (Single Element)Check fitment →

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4D95L-W-1E(S/N 11437-UP) fault codes & troubleshooting

CodeMeaningLikely causeWhat to do
CA115Engine crankshaft speed sensor and backup speed sensor failureBroken sensor, wiring issue, or connector corrosionReplace the speed sensor and verify the voltage at the pin connector
CA451Common rail pressure sensor feedback value too highMalfunction in the rail sensor or actual overpressure conditionDiagnose the fuel rail pressure sensor or pump lines
CA452Common rail pressure sensor feedback value too lowSensor malfunction or low pressure conditionDiagnose the fuel rail pressure sensor or pump lines
CA122Intake air pressure sensor feedback voltage too highSensor malfunction or wiring issueVerify the intake pressure sensor and wiring
CA123Intake air pressure sensor feedback voltage too lowSensor short or airflow restrictionCheck for a sensor short or an airflow restriction
CA153Intake air temperature sensor feedback voltage too highSensor malfunctionReplace or test the IAT sensor
CA154Intake air temperature sensor feedback voltage too lowSensor malfunctionReplace or test the IAT sensor
CA234Engine overspeedThrottle calibration error, engine load cycle issue, or operator misuseVerify throttle calibration, engine load cycle, or operator misuse
CA441Battery voltage too lowAlternator failure, battery failure, or voltage regulator issueReplace the alternator or battery; check the voltage regulator
CA442Battery voltage too highAlternator failure or voltage regulator issueReplace the alternator or battery; check the voltage regulator

Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.

4D95L-W-1E(S/N 11437-UP) attachments & work tools

Excavator Attachments

The Komatsu 4D95L-W-1E engine powers the PC60-7 series excavators (serial 45001-Up) and PC75UU-3 (serial 15001-Up). Standard work tools include digging buckets ranging from 0.25 to 0.45 cubic meters and grading or cleaning buckets of similar volume. Hydraulic breaker kits are available for these models, requiring specific high-flow hydraulic lines and mounting brackets compatible with the PC60/PC75 boom geometry.

Wheel Loader Attachments

The WA70-1 wheel loader (serial 10001-Up) utilizes the 4D95L-W-1E engine. Primary work tools are general-purpose buckets with capacities between 1.5 and 2.0 cubic meters, alongside rock buckets and wood handling forks. The machine uses a standard pin-on coupler system for quick tool changes, with hydraulic lines routed through the boom for auxiliary functions.

Engine Configuration & Guarding

The 4D95L-W-1E is a turbocharged, water-aftercooled diesel engine. Factory configurations include heavy-duty air pre-cleaners for dusty environments and specific exhaust silencer options for noise reduction. Guarding options include engine compartment screens and heat shields to protect hydraulic lines and electrical harnesses from debris and high temperatures.

All 4D95L-W-1E(S/N 11437-UP) assemblies by section

Every catalogued assembly group for the Komatsu 4D95L-W-1E(S/N 11437-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

Cooling System
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cooling System : Corrosion Resistor And Piping
01***40Bolt,(Shim 3-Piece)2
01***45Bolt, Bracket Mounting2
01***08Nut2
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cooling System : Water Pump And Cooling Fan
01***16Screw5
01***20Screw2
01***35Screw4
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Cylinder Block
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Camshaft And Tappet
01***20Screw2
04***16Fitting Wedge1
62***01Camshaft Ass'Y1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Crankshaft
61***20Bolt1
62***00Main Metal Ass'Y5
62***00Thrust Metal Ass'Y1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Cylinder Block
01***14Bolt2
01***20Screw1
01***06Nut1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Cylinder Block (Cold Terrain Spec.)
01***14Bolt2
01***20Screw1
01***25Bolt,(With Corrosion Resistor)4
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Flywheel And Flywheel Housing
01***30Bolt6
01***30Bolt - Lower Oil Cooler Outlet Tubemounting11
07***15Plug,(For Without Air Compressor)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Front Cover And Gear (For 25a Hardening Pulley Alternator) (For 35a? 50a Alternator)
01***70Bolt,(For 75a Alternator)1
01***16Bolt2
01***20Bolt,(With Tachometer Outlet)8
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Front Cover And Gear (For 25a Non Hardening Pulley Alternator)
01***70Bolt,(For 75a Alternator)1
01***16Bolt2
01***20Bolt,(With Tachometer Outlet)8
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Oil Pan
01***14Bolt24
01***16Screw24
07***23O-Ring,(F4350-61a1b-29 )1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Oil Pan (Cold Terrain Spec.)
01***14Bolt24
01***16Screw24
07***23O-Ring,(F4350-61a1b-29 )1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Block : Piston And Connecting Rod
04***12Ring, Snap8
62***00Piston Ring Ass'Y,Per Cylinder4
62***01Piston Ring Ass'Y,Per Cylinder4
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Cylinder Head
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Air Cleaner (Double Element Type) (Sandy And Dusty Spec.)
01***20Bolt,(For Japan Pc200)2
07***09Clamp, Hose - At Water Pump2
07***89Clamp,Hose2
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Air Cleaner (Single Element Type)
01***20Bolt,(For Japan Pc200)2
04***10Ring,See Fig. K4010-65a01
07***09Clamp, Hose - At Water Pump2
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Air Intake Manifold And Connection (Double Element Type) (Sandy And Dusty Spec.)
01***12Bolt,(With Speedometer)4
01***25Bolt,(With Corrosion Resistor)4
01***75Bolt,(For Shipping)8
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Air Intake Manifold And Connection (Single Element Type)
01***12Bolt,(With Speedometer)4
01***25Bolt,(With Corrosion Resistor)4
01***75Bolt,(For Shipping)8
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Cylinder Head
01***20Bolt, Hose Clamps (Inlet And Return Line Hoses)4
02***04Plug, Pipe1
07***08Plug, Expansion4
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Cylinder Head Cover
07***09Clamp, Hose2
61***10Cap, Oil Filler1
61***20Hose1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Exhaust Manifold And Muffler
01***25Grub Screw4
01***45Bolt, Bracket Mounting7
01***95Bolt,(For Shipping)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Cylinder Head : Rocker Arm
01***12Bolt,(Without R.P.C.U.)1
01***65Bolt,(For Alternator Bracket Mount)5
61***30Nut8
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Electrical System
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Alternator (35a)
60***40Alternator A. (35a)1
KD***57Bearing,Ball? Front1
KD***80Collar1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Alternator (50a)
60***90Alternator A. (50a)1
SD***X0Washer1
SD***X0Fan1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Alternator And Mounting (25a)
01***35Bolt,(Cold Weather Spec.)1
01***55Bolt,(With Engine Stop Motor Type)1
01***11Nut,(For Center Guard)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Alternator And Mounting (25a) (Tropical Sandy And Dusty Spec.)
01***35Bolt,(Cold Weather Spec.)1
01***20Screw3
01***65Bolt,(For 35a? 25a Alternator)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Alternator And Mounting (35a)
01***35Bolt,(Cold Weather Spec.)1
01***20Screw4
01***65Bolt,(For 35a? 25a Alternator)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Alternator And Mounting (50a)
01***35Bolt,(Cold Weather Spec.)1
01***25Bolt,(With Corrosion Resistor)3
01***70Bolt,(For 50a Alternator)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Heater Signal
60***61Signal,Heater1
60***80Cap1
60***90Cap3
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Starting Motor (2.8kw)
60***30Starting Motor Ass'Y,(2.8kw)1
KD***60Bracket,Center1
KD***50Stopper,Piston1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Electrical System : Starting Motor And Mounting
01***30Bolt2
07***95O-Ring,Transmission Strainer1
(6***0)Starting Motor Ass'Y,(2.8kw) (See Fig.0661)1
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Engine Kit
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Engine Kit : Gasket Kit
01***12Washer,Lock (Noise Suppression Spec.) (K2)1
07***65O-Ring,Injection Pump Case1
07***95O-Ring,Transmission Strainer1
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Fuel System
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Engine Stop Motor And Mounting
01***40Bolt,(Dust And Dirt Protection)2
01***14Bolt - Plate Mounting3
01***16Bolt - Starting Motor Ground Cable2
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Filter And Piping
01***35Bolt2
07***12Gasket,Mechanical Pump Piping1
07***12Gasket,(Without Air Compressor Type) (K1)4
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Ingection Pump (Governor) (2/2)
DK***00Spring,Governor1
DK***40Gasket,Air Compressor2
DK***00Nut,Cap1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Injection Pump (Feed Pump)
DK***20Bolt, Joint1
DK***00Valve,Check2
DK***20Pump,Priming1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Injection Pump (Governor) (1/2)
DK***00Shim? 2.00mm,(High Altitude Spec.)0
DK***00Adapter1
DK***00Nut,Lock1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Injection Pump (Pump) (1/2)
62***31Injection Pump A1
DK***30Bearing0
DK***20Shim, 1.40mm; Was Dk029311-7220, Shim? 1.4mm0
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Injection Pump (Pump) (2/2)
DK***40Shim? 0.50mm, Shim, 0.50mm; Was Dk029311-00400
DK***90Shim? 0.25mm, Shim, 0.25mm; Was Dk029311-05900
DK***00Sleeve,Control4
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Injection Pump And Piping
01***35Stud4
01***12Bolt2
01***25Screw2
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Fuel System : Fuel Nozzle And Spill Pipe
07***13Tube,Spill1
07***14Tube,Spill1
60***40Glow Plug,Glow4
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Lubricating Oil System
Komatsu : 4d95l-W-1e(S/N 11437-Up) : Lubricating Oil System : Lubricating Oil Filter
60***40Cartridge,Engine Oil Filter (D31s)1
60***41Cartridge,Engine Oil Filter (D31s)1
60***50Plate? Caution,(Russian-English)1
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Komatsu : 4d95l-W-1e(S/N 11437-Up) : Lubricating Oil System : Lubricating Oil Pump And Suction Pipe
01***12Bolt,(See Fig.0501)1
01***16Screw6
01***25Bolt,(With Corrosion Resistor)1
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4D95L-W-1E(S/N 11437-UP) serial number reference

The engine PIN plate is riveted to the engine block, typically on the left side near the injection pump or on the valve cover. Read the prefix (e.g., WA70-1) to identify the host machine family, then match the engine serial number (starting at 10001 for the 4D95L-W-1E) to confirm the specific engine variant and generation.

PrefixIdentifies
WA70-1Wheel Loader

Frequently asked questions

What engine does the Komatsu 4D95L-W-1E (S/N 11437-UP) use?

It uses the Komatsu 4D95L-W-1E, a 3.3-liter, 4-cylinder diesel engine with 45 to 60 kW (60 to 80 hp) output, part of the 95 Series family.

What is the operating weight of machines using this engine?

Operating weight varies by configuration and series. For the PC60 class, it is approximately 6,180 kg (13,624 lb). For the WA70-1 wheel loader, it ranges from 34,000 to 35,000 kg (74,957 to 77,162 lb).

What replaced the Komatsu 4D95L-W-1E?

The 4D95L-W-1E is part of the 95 Series family. It has been succeeded by newer emissions-compliant engines in the SAA4D95LE and SA6D102E families for modern excavator and loader models.

What 4D95L-W-1E(S/N 11437-UP) owners discuss

What is the primary powertrain and hydraulic behavior associated with the Komatsu 4D95L-W-1E engine in WA70-1 wheel loaders?
The WA70-1 wheel loader equipped with the 4D95L-W-1E engine (serial 11437-Up) utilizes a mechanical fuel injection system without an electronic control unit (ECU). The engine is turbocharged and features a direct injection fuel system. Hydraulic performance is governed by the machine's main pump and control valves rather than engine electronics, meaning hydraulic weakness when hot typically indicates internal pump or valve leakage rather than an engine management fault. Engine speed remains stable under load unless the hydraulic system places excessive demand on the power source.
What are the typical undercarriage and wear patterns for the WA70-1 wheel loader series?
The WA70-1 series is a mid-size wheel loader with an operating weight class between 34,000 and 35,000 lb. Typical wear patterns include rapid undercarriage degradation in abrasive environments, track tension loss due to frequent cycling, and final drive noise from contaminated axle oil. The machine is prone to pulling to one side if track tension or roller condition differs between sides. Hydraulic filters and engine air filters require frequent inspection due to dust exposure, which directly impacts engine power and hydraulic responsiveness.
What are the known engine quirks for the 4D95L-W-1E series compared to earlier 4D95 variants?
The 4D95L-W-1E series (serial 11437-Up) is part of the later generation of the 4D95 family, often cross-referenced with the Cummins B3.3T. Unlike earlier mechanical-only 4D95 models, this series may incorporate updated emissions packaging but retains the mechanical injection architecture in many configurations. A key quirk is sensitivity to fuel quality; air entering the fuel supply or degraded fuel filters can cause intermittent starting or power loss under load. The engine does not use common rail injection; each injector has its own line from the pump, making individual injector line integrity critical for smooth operation.
What are the common electrical and sensor issues reported for machines using this engine?
While the 4D95L-W-1E engine itself is mechanically controlled, the host machine (WA70-1) relies on electronic control systems for operation. Common issues include intermittent starting, dashboard failures, and random shutdowns caused by unstable power supplies or faulty sensors. Grounding issues between the engine and chassis are frequent culprits for erratic behavior. Battery state of charge must be verified under load, as voltage collapse during cranking can mimic starter failure. Multiple fault codes often point to battery or ground connector issues rather than component failure.
What should be checked when buying a used WA70-1 with the 4D95L-W-1E engine?
Verify the engine serial number is 11437-Up to confirm the 4D95L-W-1E configuration. Check for exhaust in the cooling system, which indicates a blown head gasket or cracked liner, a known failure mode for higher serial number 4D95 engines. Inspect hydraulic oil condition and temperature behavior; weak hydraulics when hot suggest internal leakage. Test travel speed on both tracks to identify final drive or motor issues. Check the air intake and charge-air hoses for cracks or loose clamps, which cause power loss. Verify the condition of the fuel filters and water separator, as clogged filters are a primary cause of starting difficulties.
What are the fluid specifications and capacity considerations for this engine?
Use Komatsu EO or equivalent diesel engine oil for lubrication. Hydraulic oil must meet Komatsu specifications to prevent pump wear and maintain performance across temperature ranges. Coolant should be Komatsu Super-coolant AF-NAC or equivalent. The engine displacement is approximately 3.3 liters. Fluid capacities vary by configuration; consult the operation and maintenance manual for the WA70-1 series for exact volumes. Do not mix fluid types, as incorrect hydraulic oil can lead to cavitation and component failure.
What safety-critical fix is associated with the cooling system on this engine?
If coolant is repeatedly expelled or the system becomes highly pressurized shortly after a cold start, the head gasket or cylinder liner may be compromised. This can lead to exhaust gases entering the cooling system, causing overheating and potential engine damage. Have your dealer verify the integrity of the head gasket and cylinder liners before further operation.

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

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