Komatsu WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP)
Komatsuwheel loadersmall ( - wa120 / sk*)

Komatsu WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP)

Maintenance schedule, common problems & OEM parts breakdown

Search live WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) parts

The Komatsu WA75-3 and WA85-3 are compact wheel loaders from Komatsu's German-built -3 series, produced from roughly 1998 into the mid-2000s. The WA75-3 runs a 4-cylinder, mechanically injected diesel rated around 42.5 kW (58 PS); the WA85-3 steps up to a related 4-cylinder diesel rated around 48 kW (65 PS). Operating weight spans about 4,880 kg (10,760 lb) for the WA75-3 to roughly 5,210 kg (11,490 lb) for the WA85-3, with bucket capacities from about 0.75 to 1.25 m3 (1.0 to 1.6 cu yd) depending on configuration. This 30 km/h option build adds a two-speed transfer gearbox behind the standard closed-circuit hydrostatic (HST) drive unit, versus the base 20 km/h machine. Confirmed predecessor and successor models are not documented for this exact serial break — verify lineage with your dealer.

Komatsu's -3 series brought closed-circuit HST drive to this loader class, giving stepless speed control and strong tractive effort without a torque-converter powershift box. The 30 km/h transfer gearbox option targets operators moving the loader between job sites on public roads, trading a bit of driveline simplicity for road speed versus the base 20 km/h build. Both axles carry a limited-slip differential (about 25% locking) for consistent traction on loose or uneven ground. Because these loaders predate electronic engine and transmission controls, they remain attractive in the used and parts market: mechanical injection, HST components, and axle parts are straightforward to service and rebuild without ECM diagnostics, which keeps repair costs predictable on older units still working yards and quarries today.

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 WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) specifications

Engine

Engine modelKomatsu 4D98E, 4-cylinder direct-injection diesel. Same base engine used on the WA75-3 and WA85-3, tuned to two different power ratings.
WA75-3 net power42.5 kW / 58 PS (57 hp) at 2,500 rpm, per ISO 9249
WA85-3 net power48 kW / 65 PS (64 hp) at 2,500 rpm, per ISO 9249
Max torqueWA75-3: 210 Nm (155 lb-ft) at 1,600 rpm. WA85-3: 240 Nm (177 lb-ft) at 1,600 rpm
Displacement / cylinders3.318 L (202.5 cu in), 4 cylinders, bore x stroke 98 x 110 mm (3.86 x 4.33 in)
Combustion / coolingDirect injection. Dual-circuit liquid cooling, thermostat-controlled
EmissionsCertified to EC Stage II and ISO 6393. Factory exhaust test values (ISO 8178 method) run well under the EC Stage II limits for CO, HC and NOx

Weights

WA75-3 operating weight4,880 kg (10,758 lb) with standard 0.8 m³ bucket; up to 5,245 kg (11,563 lb) with larger buckets/attachments fitted
WA85-3 operating weight5,210 kg (11,486 lb) with standard 0.9 m³ bucket; up to 5,530 kg (12,191 lb) with larger buckets/attachments fitted
Weight notesOperating weight varies by bucket, counterweight and axle-weight options; figures above are factory baseline configurations. Some third-party listings for the base (non-30 km/h) trim run slightly lower, roughly 4,850-5,000 kg -- treat as variance by configuration/series, not a contradiction
Ground pressureNot published for this configuration -- check with a dealer for a tyre-specific figure if needed
Shipping weightNot separately published; factory data sheets list operating weight only

Dimensions

WA75-3 overall length5,395 mm (17.7 ft / 212 in), standard bucket resting on ground
WA85-3 overall length5,380 mm (17.7 ft / 212 in), standard bucket resting on ground
Overall heightWA75-3: 2,640 mm (8.7 ft / 104 in) to cab top. WA85-3: 2,665 mm (8.7 ft / 105 in) to cab top
Wheelbase2,000 mm (6.6 ft / 78.7 in), both models
Track gauge1,550 mm (5.1 ft / 61 in), both models
Ground clearanceWA75-3: 450 mm (17.7 in). WA85-3: 475 mm (18.7 in)
Bucket width (standard)WA75-3: 1,950 mm (6.4 ft / 76.8 in) with 0.8 m³ bucket. WA85-3: 2,050 mm (6.7 ft / 80.7 in) with 0.9 m³ bucket
Turning radiusOver bucket corner: WA75-3 4,210 mm (13.8 ft), WA85-3 4,260 mm (14.0 ft). Minimum steering turning radius (outer tyre corner): WA75-3 3.77 m (12.4 ft), WA85-3 3.79 m (12.4 ft)
ArticulationArticulated/oscillating frame joint, +/-12 degrees oscillation, 40 degree steering swing to either side

Performance

Travel speed, 1st gearWA75-3: 0-7.5 km/h (0-4.7 mph). WA85-3: 0-5.7 km/h (0-3.5 mph)
Travel speed, 2nd gear0-20 km/h (0-12.4 mph), both models, standard transmission
Travel speed, 30 km/h option0-30 km/h (0-18.6 mph) with the high-speed transmission option fitted to this serial range, both models
TransmissionHydrostatic, full-power shifting in all directions, 2 forward / 2 reverse gears
Max breakout forceUp to 48.6 kN (10,926 lbf) with standard bucket, both models; decreases with larger bucket sizes
Max static lifting capacity38.7 kN (8,700 lbf) with standard bucket, both models
Hydraulic cycle timesLift 4.9 s, lower 2.6 s, dump 1.0 s, both models
Steering systemArticulated-frame, closed-center hydrostatic steering, 175 bar working pressure
GradeabilityNot published for this configuration

Service capacities (summary)

Fuel tank90 L (23.8 gal), both models
Hydraulic system95.0 L (25.1 gal) for attachment, steering and motive-power hydraulics, both models
Engine oil9.4 L (2.5 gal), both models
Cooling system12.25 L (3.2 gal), both models
Front axle6.1 L (1.6 gal), both models
Rear axle (with transmission gears)6.5 L (1.7 gal), both models

Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.

WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) fluids & capacities

SystemCapacityRecommended fluid
Engine crankcase (with filter)9.4 L (2.5 US gal)Komatsu genuine engine oil (EO series), API CD/CE or higher. Select grade by ambient temperature: SAE 10W in cold climates below about -15°C, 10W-30 for general/moderate range use, 15W-40 or straight 30 grade in warmer climates. Recheck level after a filter change with engine run and shut down.
Cooling system12.5 L (3.3 US gal)Komatsu genuine permanent-type antifreeze coolant (ethylene glycol base), pre-mixed or diluted with clean water to the ratio needed for local freeze protection. Do not mix coolant types or brands.
Fuel tank90 L (23.8 US gal)No. 2-D diesel fuel meeting ASTM D975 or equivalent local spec. Switch to a winter-grade or kerosene-blended fuel in cold climates to prevent wax/gelling.
Torque converter & transmissionNot separately published for this configuration in available capacity references — confirm exact fill with the dealer or full O&M manual chartKomatsu genuine Powertrain Oil (TO series, e.g. TO30 grade), SAE 30 single-viscosity powershift transmission fluid.
Final drives (front/rear)Integrated into the front/rear axle housing oil volume below; no separate final-drive fill point is published for this loader size classSame axle oil as the axle housing (see Front axle/differential and Rear axle/differential rows).
Hydraulic system (tank + circuit)95.0 L (25.1 US gal) total system, tank included; tank-only volume not separately publishedKomatsu genuine Hydraulic Oil (HO series). Grade by ambient temperature: lighter cold-climate grade (SAE 10W type) in low temperatures, heavier grade (SAE 30 / ISO VG46-equivalent) in temperate-to-warm climates.
Front axle/differential6.4 L (1.7 US gal)Komatsu genuine Axle Oil (AXO series), SAE 80W-90, API GL-4/GL-5, limited-slip compatible.
Rear axle/differential6.8 L (1.8 US gal)Komatsu genuine Axle Oil (AXO series), SAE 80W-90, API GL-4/GL-5.
Grease (chassis lubrication points)Spec only — no reservoir capacityKomatsu genuine multipurpose lithium EP grease (G2-LI type) at all pin, bushing, and steering-linkage grease points per the lubrication chart interval.

Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.

Komatsu WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) maintenance schedule

Service intervalTasks
Every 10 h
  • Check engine oil level before startup and top up if below the low mark
  • Check coolant level in the sub-tank and inspect the radiator and grille for debris
  • Check hydraulic oil level at the tank sight gauge with the boom lowered and engine off
  • Check HST reservoir oil level and look for leaks at hose fittings and the transfer gearbox case
  • Walk around the loader and inspect tires, the articulation joint, and boom pins for damage or looseness
  • Weekly (every 50 h): grease articulation, boom, and bucket linkage pins, and drain water and sediment from the fuel water separator
Every 250 h
  • Change engine oil and replace the oil filter cartridge
  • Check front and rear axle oil levels and top up with the specified gear oil
  • Check transfer gearbox oil level on 30 km/h option units
  • Inspect V-belt tension and condition, adjust or replace as needed
  • Check battery electrolyte level and clean terminals
  • Inspect brake pedal free travel and parking brake operation
Every 500 h
  • Replace the fuel filter element and bleed the fuel system
  • Replace the hydraulic tank breather and return filter element
  • Replace the engine air cleaner safety element if the restriction indicator shows red
  • Check the HST charge-pump line filter and clean or replace it
  • Clean the radiator, oil cooler, and condenser fins with compressed air
  • Check wheel nut torque and steering linkage play
Every 1,000 h
  • Change front and rear axle differential and final drive oil
  • Change the transfer gearbox oil on 30 km/h option units
  • Drain and inspect engine coolant, replace if condition warrants
  • Inspect and adjust fuel injection nozzles on the mechanical injection system
  • Check alternator and starter motor brushes and connections
  • Inspect king pin and steering cylinder pins for wear
Every 2,000 h
  • Change hydraulic tank oil and bleed air from the hydraulic circuit
  • Replace the HST closed-circuit oil and its filter
  • Inspect hydraulic hoses for cracking or chafing and replace as needed
  • Check the water pump and fan drive for play or leakage
  • Inspect the limited-slip differential clutch packs for wear in both axles
  • Retorque wheel rim bolts and check axle mounting bolts
Every 4,000 h
  • Inspect and, if worn, rebuild the HST pump and motor units
  • Overhaul or replace axle planetary hub bearings and seals as wear dictates
  • Perform a top-end engine inspection covering injection pump timing, valve clearance, and compression
  • Inspect and rebuild the two-speed transfer gearbox shift mechanism on 30 km/h option units
  • Replace articulation joint bushings and king pins if play exceeds service limits

Servicing the WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) beyond the schedule

Predictive Maintenance & Fluid Analysis

Sample HST closed-circuit oil and transfer gearbox oil at scheduled changes; wear metals in the transfer case flag early gear or bearing distress in the 30 km/h option's added driveline stage. Track engine oil condition closely since the mechanically injected 4-cylinder diesel carries no ECM to flag drift — rely on oil analysis and injector spray-pattern checks instead. Watch limited-slip differential oil in both axles for clutch-pack wear metal before it shows up as reduced traction.

Corrective & Common Repairs

Expect HST charge-pump and relief-valve wear as the most common drivetrain complaint, showing up as sluggish response or loss of drive power. The 30 km/h option's two-speed transfer gearbox shift linkage and synchronizer are a known wear point versus base 20 km/h units. The mechanical injection pump and nozzles need periodic recalibration for a smooth idle. Also check articulation joint bushings and center pin play, a common fault on high-hour yard machines.

Overhaul & Rebuild Points

Major rebuild targets are the HST pump and motor pair, front and rear axle planetary hubs, and the limited-slip differential clutch packs in both axles. On 30 km/h option units, the transfer gearbox gearset and synchronizer wear faster than on base machines and warrant inspection at major overhaul. The mechanically injected engine responds well to a straightforward top-end rebuild — injection pump, nozzles, valve train — without emissions-era electronics to complicate the job.

Seasonal & Environment Servicing

Cold climates demand engine oil and HST fluid viscosity matched to ambient temperature; this mechanically injected diesel has no glow-plug electronics, so cold starting depends on correct fuel and oil grade plus a working intake heater. Warm up the HST circuit before full-load work in freezing conditions. In hot, dusty environments, clean the radiator, oil cooler, and air intake more often, and inspect the transfer gearbox breather for clogging on the 30 km/h option build.

WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) common service parts

Part numberPart
42U-62-12200FilterCheck fitment →
42U-62-13150Filter ElementCheck fitment →

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

WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) fault codes & troubleshooting

CodeMeaningLikely causeWhat to do
Brake fluid warning lightBrake fluid level in the reservoir has dropped below the safe minimum, or hydraulic brake circuit pressure is low.Low fluid level from normal pad wear, an external leak at a line or wheel end, or a failing brake fluid level switch.Stop and park safely, check reservoir level, inspect brake lines and wheel ends for leaks, top up to spec before resuming work.
Air filter warning lightAir intake restriction across the air cleaner has exceeded the allowable limit.Clogged or dirty air cleaner element, blocked intake ducting, or a damaged element letting dust bypass the service indicator.Shut down, inspect and clean or replace the air cleaner element, reset the restriction indicator, verify ducting is sealed.
Parking brake warning lightIndicates the parking brake is set/engaged; it is a status telltale rather than a fault by itself.Parking brake lever left engaged before attempting to drive, or the brake failing to release fully due to linkage or cable binding.Confirm the parking brake lever is fully released before moving the machine; if the light stays on with the lever released, inspect the parking brake cable, linkage, or switch.
Charging current warning lightAlternator is not charging the battery (charging circuit fault).Broken or slipping fan/alternator belt, faulty alternator, loose or corroded wiring, or a blown fuse in the charge circuit.Stop and check belt condition and tension, inspect wiring connections and alternator output; do not keep operating with the light on, the battery will discharge.
Engine oil pressure warning lightEngine lubrication pressure is too low. Normally lights with the key on and goes out shortly after start; lighting during operation means inadequate oil pressure.Low engine oil level, clogged oil filter, worn oil pump, or a failed oil pressure sensor/switch.Stop the engine immediately, check oil level and filter condition, do not restart or keep running until the cause is found and corrected.

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

WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) attachments & work tools

Earth-moving / general-purpose bucket

Standard bucket is 0.8 m³ (1.05 cu yd) heaped on the WA75-3 and 0.9 m³ (1.18 cu yd) on the WA85-3; factory bucket range for the class runs 0.75-1.25 m³ (0.98-1.63 cu yd) depending on type. Standard bucket breakout force runs up to about 48.6 kN (10,900 lbf) and mounts on the factory quick coupler.

Light-material bucket

Larger, shallower bucket at 1.0-1.25 m³ (1.31-1.63 cu yd) for low-density loose material such as mulch or grain. Trades breakout force for extra volume compared with the standard earth-moving bucket.

4-in-1 (universal) bucket

Combination clamshell-jaw bucket rated 0.65-0.75 m³ (0.85-0.98 cu yd) across the two models; used for dozing, grading, loading, and light clamping in one tool. Lower breakout force than the plain bucket due to the added jaw mechanism.

High-dump bucket

1.25 m³ (1.63 cu yd) bucket for dumping over truck sideboards or into hoppers, reaching roughly 3.9-4.0 m (12.8-13.1 ft) dump height at maximum angle. Lowest breakout force in the bucket range, around 24 kN (5,400 lbf).

Side-dump, skeleton, and mulch-grab/stockpile buckets

Side-dump bucket (about 0.8 m³ / 1.05 cu yd) discharges sideways for tight-space stockpiling; skeleton (screening) bucket sifts fines from rock and debris. Mulch grab / stockpile bucket (about 0.8-1.0 m³ / 1.05-1.31 cu yd) adds a hydraulic grapple top for loose organic or bulky material.

Fork carrier and pallet tines

Factory fork carrier with tines mounts on the standard quick coupler; rated payload is about 1.55-1.65 t at the EN 474-3 60% stability limit and 2.0-2.1 t at the 80% limit, varying by model. Fitting the bolt-on rear counterweight option is recommended when running forks to hold rated capacity and stability.

Quick-coupler / mounting system

Both models carry a hydraulic 4-point quick coupler as standard equipment, sized for the full range of factory original attachments and stated as usable with other manufacturers' tools too. An electro-hydraulic coupler lock and electric actuation of the auxiliary circuit are offered as options for cab-operated tool changes.

Auxiliary hydraulic circuit and ride-control options

A 3rd hydraulic control circuit for attachment power is standard equipment, required for tools such as the sweeper, telescopic crane arm, grapple bucket, and 4-in-1 bucket. Optional over-centre (load-holding) valve and an automatic load stabiliser (boom ride-control) are offered for smoother handling with buckets and forks.

Telescopic crane arm and sweeper

Optional telescopic crane arm mounts through the standard coupler and runs off the auxiliary circuit for suspended-load lifting within the loader's rated tipping capacity. Optional rotary sweeper (broom) attachment also runs off the 3rd circuit for yard and road-surface work.

Stability/counterweight and speed-related factory options

Additional front-axle weight kits (about 70 kg / 154 lb per side) and a rear bolt-on counterweight (about 100 kg / 220 lb) are factory options to offset attachment loads, most relevant when running forks or heavier buckets. This configuration is built with the optional 30 km/h high-speed transmission alongside the base 2-range (low-speed/20 km/h) travel system; the higher road speed does not change attachment fitment or the coupler type.

All WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) assemblies by section

Every catalogued assembly group for the Komatsu WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

03 Electric System
Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 03 Electric System : 63 Instrument Box And Instruments
42***01Key Kit1
42***10Starter Switch1
42***30Symbol1
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Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 03 Electric System : 80 Licence Plate Light
01***10Screw,(For Lighter)4
01***16Screw, Mount Parking Lights2
42***00Licence Plate Light2
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04 Transmission, Universal Joint
Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 04 Transmission, Universal Joint : 61 Axial Piston Pump
42***01Axial Piston Pump1
42***51Axial Piston Pump1
42***74Pump1
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Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 04 Transmission, Universal Joint : 75 Universal Joint
01***20Bolt, Wiring Harness Mounting Bracket6
42***00Universal Joint1
42***20Screw6
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Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 04 Transmission, Universal Joint : 93 Gear Box Controls
01***45Screw4
01***22Screw2
01***25Bolt,L.H. (For Add. Air Compressor)2
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Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 04 Transmission, Universal Joint : 97 Hydraulic Pump Drive
01***45Screw2
01***50Screw2
01***20Screw4
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Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 04 Transmission, Universal Joint : 98 Axial Piston Engine
42***62Grub Screw2
42***11Axial Piston Engine1
42***58Plug2
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05 Rear Axle
Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 05 Rear Axle : 43 Rear Axle
01***16Nut - M208
01***60Flat Washer - M20 (Hardened)8
42***10U Bolt4
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Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 05 Rear Axle : 46 Brake
42***02Grub Screw2
42***70O-Ring1
42***71Bushing2
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12 Tools, Accessory, Lettering
Komatsu : Wa75-3(30km/H Option S/N Ha950051-Ha951433 & H21408-Up; Wa85-3 30km/H Option S/N Ha960051-Ha960218 & H20219-Up) : 12 Tools, Accessory, Lettering : 03 Lettering
09***60Decal, Komatsu (Black Lettering) (Behind Driver'S Door)2
42***20Characters2
42***50Note Plate4
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WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) serial number reference

The PIN/serial plate on the WA75-3 and WA85-3 is riveted to the right (curb) side of the machine frame behind the front fender, with a duplicate stamped into the frame steel nearby; on some units it also shows under the right side of the operator's cab. Read the letter-prefixed number (HA95.../HA96...) as the worldwide chassis serial identifying the base model line, and treat any separate all-numeric H2..... number on the same plate or dataplate as the North America production/running serial paired to that chassis - both numbers should be checked against the parts book breakpoint when ordering.

PrefixIdentifies
HA95WA75-3 30km/h option wheel loader, chassis serial series
HA96WA85-3 30km/h option wheel loader, chassis serial series
H21WA75-3 30km/h option, North America running-serial series
H20WA85-3 30km/h option, North America running-serial series

Frequently asked questions

What engine powers the Komatsu WA75-3 / WA85-3 (30 km/h option)?

The WA75-3 and WA85-3 share the same Komatsu 4D98E-family four-cylinder, mechanically injected diesel block, tuned differently: the WA75-3 to about 42.5 kW (58 PS), the WA85-3 to about 48 kW (65 PS), per the factory data sheet.

What is the operating weight of the WA75-3 / WA85-3 (30 km/h option)?

Operating weight runs roughly 4,880 kg (10,760 lb) for the WA75-3 and about 5,210 kg (11,490 lb) for the WA85-3, varying with bucket and counterweight configuration.

What replaced the Komatsu WA75-3 / WA85-3 (30 km/h option)?

No confirmed successor model is documented for this specific serial range. Please verify the direct replacement model with your Komatsu dealer.

What WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP) owners discuss

Is the WA75-3/WA85-3 drive a torque-converter powershift or something else, and does the 30 km/h option change that?
Both machines use a closed-circuit hydrostatic drive: a variable-displacement pump feeding a variable-displacement motor, not a torque converter and powershift gearbox. On the 30 km/h option covered here, a two-speed distributor (transfer) gearbox sits behind the HST unit so the loader can run up to 30 km/h (about 18.6 mph) on the road instead of the standard 20 km/h (about 12.4 mph) top speed. Owners report creeping in neutral or a jerky feel on direction changes; before assuming a pump rebuild, check charge pressure and the torque on the pump-to-housing mounting bolts — a loose pump mount is a common and cheap fix for jerkiness. Have your dealer verify charge pressure specs before adjusting.
What engine is under the hood, and does it differ between the WA75-3 and WA85-3?
Both share the same Komatsu 4D98E-family four-cylinder diesel block, tuned differently: the WA75-3 is rated around 42.5 kW (58 PS), the WA85-3 around 48 kW (65 PS). Both use mechanical (jerk-pump style) fuel injection - no electronic engine control and no aftertreatment, which owners like for simple field diagnosis. Because there's no electronic idle or fuel management, cold-start performance rides entirely on the glow-plug/pre-heat circuit and battery condition. Hard cranking or white smoke on a cold start is usually weak glow plugs or a tired battery on these engines, not a fuel-system fault.
What wears out first on the undercarriage/drivetrain of this loader?
These are articulated-frame loaders, so there is no track undercarriage — wear concentrates at the center articulation pin and bushings. Have a second person cycle the steering while you watch and feel the joint for play, and keep it greased on the scheduled interval; missed grease points are a common owner complaint. Both front and rear axles carry a limited-slip differential (about 25% locking) as standard, appreciated for wet or loose yard surfaces. A diff that will not lock, or one wheel spinning freely under load, usually points to a worn LSD clutch pack rather than a broken axle. Have your dealer verify pivot pin clearance and diff lock-up before returning the machine to heavy work.
Any known electrical/sensor gremlins or ignition quirks?
These loaders come from Komatsu's German-built compact-loader line, and that shows up in the ignition system: the common Komatsu universal key that starts most of the wider range does not fit the WA65/WA75/WA85/WA95 family — a separate lock cylinder is used, worth knowing before cutting a spare key. The instrument panel is basic warning-light style (charging, engine oil pressure, parking brake, air filter, brake fluid) rather than a digital monitor, so most electrical complaints trace back to a failed sender, a corroded ground, or a tired alternator rather than a control-module fault.
The hydraulic/cooling system runs hot under sustained loading — is that normal?
Compact loaders like this pack a small radiator and oil cooler into a tight engine bay relative to engine output, so the cooling stack has little margin for dirt or debris. Owners note that temperature climbs gradually over a shift rather than spiking suddenly, and the fix is almost always clearing the cooler fins and checking hydraulic oil level/condition before suspecting the pump or motor. Persistent overheating after a clean cooler and correct fluid level points to internal leakage in the HST circuit or a worn charge pump — that is a job for a shop with pressure-test gauges, not a DIY fix.
What should I check before buying a used WA75-3/WA85-3 with the 30 km/h option?
Confirm the data plate and serial actually carry the 30 km/h option — a standard 20 km/h unit lacks the extra distributor gearbox behind the HST drive, and running-gear parts are not interchangeable between the two. Verify the fitted engine matches the model (both use the 4D98E-family block, tuned to different power ratings by model); engines get swapped or rebuilt with mixed parts over 20-plus years. Cycle the drive through both speed ranges checking for smooth engagement and no unusual noise from the transfer box. Check center-pin/bushing play, confirm limited-slip lock-up on both axles, test glow-plug cold start, and inspect the radiator/oil cooler stack for damage or heavy dirt loading. Confirm the ignition key is the correct Hanomag-line lock, not a generic Komatsu key. Have your dealer verify parking brake holding force and HST charge pressure before putting the machine into daily service.

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

Serial-range & configuration variants

This page covers the Komatsu WA75-3(30km/h Option S/N HA950051-HA951433 & H21408-UP; WA85-3 30km/h Option S/N HA960051-HA960218 & H20219-UP). Related factory variants of the same model family:

WA75-3(S/N HA950051-HA950856; WA85-3 S/N HA960051-HA960165)WA75-3(S/N HA950857-HA951433 & H21408-UP; WA85-3 S/N HA960166-HA960218 & H20219-UP)

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