Komatsumotor grader(no series)
Komatsu GD750A-1(S/N 7001-UP)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu GD750A-1 is a large-frame articulated motor grader built around a Cummins M11-C six-cylinder turbocharged diesel of 10.8 L displacement, using a mechanical PT (Pressure-Time) governed fuel system rather than an electronically controlled engine, rated 183 kW (245 HP) gross and 168 kW (225 HP) net at 2000 rpm. Operating weight runs around 19,050 kg (42,000 lb) in four-wheel-drive trim with full fluids and a standard 4267 mm (14 ft) moldboard, with a 4877 mm (16 ft) moldboard offered as an option. Drive is through an 8-speed forward/4-speed reverse powershift transmission with a torque-converter lock-up clutch, and the articulated frame allows the blade to be positioned 90 degrees to either side. Factory literature for this serial range is dated 1999 and used machines from this run show up with 1998 build dates, placing the GD750A-1 in Komatsu's mid-to-late-1990s large motor grader offering. A documented predecessor or direct numbered successor for this exact S/N 7001-UP range is not confirmed in available factory documentation.
Within the GD750A-1 run, published operation and maintenance manuals reference two overlapping serial windows (S/N 7001-UP and a later 7003-UP printing), which mainly reflect running production changes and manual reprints rather than a distinct model generation. What sets this era of large Komatsu grader apart is the mechanical, non-electronic Cummins M11-C fuel system: there is no engine ECM or stored fault-code diagnostics, so condition monitoring leans on oil, fuel, and coolant sampling rather than a service tool readout. That simplicity is a large part of why the GD750A-1 still holds value in the used and parts market today. Its drivetrain, tandem cases, circle drive, and hydraulic components are mechanically straightforward to diagnose and rebuild, and the machine remains a working platform in road-maintenance, aggregate, and civil earthmoving fleets where a rugged, low-electronics grader is preferred over newer, more instrumented models.
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 GD750A-1(S/N 7001-UP) specifications
Engine
| Engine model | Cummins M11-C |
| Type | 4-cycle diesel, turbocharged, 6 cylinders |
| Bore x stroke | 125 mm x 147 mm (4.92 in x 5.79 in) |
| Piston displacement | 10.8 L (661 in3) |
| Gross power | 183 kW (245 HP) @ 2000 rpm, per SAE J1995 |
| Net flywheel power | 168 kW (225 HP) @ 2000 rpm, per SAE J1349 |
| Peak torque | 1,125 Nm (830 lb-ft) @ 1,300 rpm, 29% torque rise |
| Air cleaner | 2-stage dry-type, dual element with precleaner |
| Electrical system | 24V, 50A alternator, two 12V batteries (1,000 CCA each) |
| Emissions tier | Not documented for this serial range - verify with your dealer |
Weights
| Operating weight (total) | 19,050 kg (42,000 lb) - includes lubricants, coolant, full fuel tank, and operator |
| Weight on front wheels | 5,575 kg (12,300 lb) |
| Weight on rear wheels | 13,925 kg (30,700 lb) |
| Ground pressure | Not published for this wheeled grader |
Dimensions
| Overall height | 3,353 mm (11'0") |
| Overall width (standard) | 2,743 mm (9'0") |
| Overall transport length (with optional 16 ft moldboard) | 10,668 mm (35'0"); standard-length figure with the 14 ft moldboard not separately published |
| Ground clearance at front axle pivot | 635 mm (25 in) |
| Tandem wheel axle spacing | 1,626 mm (64 in) |
| Moldboard (standard) | 4,267 x 686 x 25 mm (14 ft x 27 in x 1 in), 432 mm (17 in) arc radius, blade base 2,870 mm (113 in) |
| Moldboard (optional) | 4,877 x 686 x 25 mm (16 ft x 27 in x 1 in), 17 in arc radius |
| Circle diameter (outside) | 1,816 mm (71.5 in) |
| Maximum cutting depth | 775 mm (30.5 in) |
| Maximum lift above ground | 473 mm (18.6 in) |
| Wheel lean angle | 17 deg, right or left; total oscillation 32 deg |
Performance
| Travel speed, forward | Gear 1: 4.2 km/h (2.6 mph); Gear 2: 5.8 km/h (3.6 mph); Gear 3: 8.2 km/h (5.1 mph); Gear 4: 11.4 km/h (7.1 mph); Gear 5: 16.4 km/h (10.2 mph); Gear 6: 23.0 km/h (14.3 mph); Gear 7: 32.0 km/h (19.9 mph); Gear 8: 44.9 km/h (27.9 mph) - at rated engine speed |
| Travel speed, reverse | Gear 1: 4.2 km/h (2.6 mph); Gear 2: 8.2 km/h (5.1 mph); Gear 3: 16.4 km/h (10.2 mph); Gear 4: 32.0 km/h (19.9 mph) - at rated engine speed |
| Transmission | Full power shift with integral free-wheeling stator torque converter and lock-up; automatic direct-drive lock-up in gears 5-8 |
| Minimum turning radius | 7.9 m (25'11") |
| Steering range | 50 deg right or left; articulation 22 deg right or left |
| Gradeability | Not published in available literature |
Service capacities (summary)
| Fuel tank (usable) | 379 L (100.0 US gal) |
| Cooling system | 64 L (17.0 US gal) |
| Engine oil (crankcase) | 13 L (3.4 US gal) |
| Transmission | 42 L (11.0 US gal) |
| Hydraulic system (total) | 136 L (36.0 US gal), of which hydraulic tank holds 51 L (13.5 US gal) |
| Tandem housing (each side) | 89 L (23.5 US gal) |
| Circle drive housing | 9 L (2.5 US gal) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
GD750A-1(S/N 7001-UP) fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | 13 L (3.4 US gal) | Komatsu genuine engine oil (EO series) meeting the diesel spec for the Cummins M11-C engine fitted to this grader. OMM ambient-temperature chart calls for a lighter grade (about 10W-30) in cold conditions and a heavier grade (about 15W-40) in warm conditions. |
| Cooling system | 64 L (16.9 US gal) | Komatsu genuine antifreeze coolant, ethylene-glycol based, pre-mixed. Follow the OMM ambient-temperature chart for correct concentration/protection level. |
| Fuel tank | 379 L (100.0 US gal) | Diesel fuel meeting the Cummins M11-C engine's fuel spec; use low-sulfur diesel per local emissions requirements. |
| Power train case (transmission) | Not documented for this exact serial range in available sources — verify with your dealer OMM chart | Komatsu genuine powertrain oil (TO series, TO-4 type), the standard fill for Komatsu power-shift transmissions in this machine class. A lighter-viscosity grade of the same TO series applies in cold climates. |
| Tandem drive case, each side | About 89 L (23.5 US gal) per side per factory spec data — cross-check against your OMM before service | Komatsu genuine powertrain oil (TO series, TO-4 type), same family as the power train case; lighter-viscosity grade for cold climates. |
| Circle drive housing | 9 L (2.4 US gal) | Komatsu genuine powertrain oil (TO series), same spec as the tandem drive cases. |
| Front axle | Not documented for this exact serial range in available sources — verify with your dealer OMM chart | If the front axle carries a driven differential, Komatsu genuine axle oil (AXO series, GL-4 rated) is the standard spec for this grader class. On many graders in this series the front axle is steering-only, with grease-lubricated wheel bearings instead of a differential fill. |
| Hydraulic system and tank | Tank refill about 51 L (13.5 US gal); total system including cylinders and lines about 136 L (35.9 US gal) | Komatsu genuine hydraulic oil (HO series), standard viscosity grade for normal/warm climates, with a lower-viscosity arctic grade specified for cold climates in the OMM chart. |
| Grease, all points | Spec only — no fill capacity applicable | Komatsu multipurpose lithium EP grease (G2-LI family); low-temperature version of the same family for cold-climate service. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Komatsu GD750A-1(S/N 7001-UP) maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 50 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the GD750A-1(S/N 7001-UP) beyond the schedule
Predictive Maintenance & Fluid Analysis
Because the Cummins M11-C runs a mechanical PT fuel system with no ECM fault logging, oil and fluid sampling carries more of the diagnostic load on this grader. Pull engine oil samples to catch early injector and fuel-pump wear, run coolant SCA tests to protect the wet liners, and sample transmission/torque-converter oil to catch powershift clutch wear before it causes lock-up slip. Tandem case, circle drive, and hydraulic oil samples flag gear and pump wear metal ahead of failure.
Corrective & Common Repairs
Typical GD750A-1 repairs center on the wear points created by constant blade articulation and side-shift: circle drive wear shoes and ring gear, drawbar ball-and-socket looseness causing blade chatter, and articulation hitch pin and bushing wear from full left-right frame swing. Front wheel bearing play and tandem case wear also show up on higher-hour machines. Moldboard cutting edges, end bits, and scarifier teeth are routine wear-item replacements on grading-duty units.
Overhaul & Rebuild Points
Major rebuild work on the GD750A-1 usually targets the PT fuel pump and injectors, which need periodic recalibration since there is no electronic self-diagnosis on the M11-C. Powershift transmission and torque converter clutch packs are the other common overhaul item at high hours. Structural inspection of the circle frame, drawbar, and articulation hitch for cracking is warranted given the sustained bending loads from blade grading work, along with front axle king-pin and wheel bearing overhaul.
Seasonal & Environment Servicing
Ahead of cold weather, check coolant glycol ratio and SCA level for the M11-C and verify the starting aid system, since this engine predates electronic cold-start strategies. In wet or humid road-maintenance work, drain the fuel/water separator more often to protect the mechanical PT pump from water contamination. In dusty grading environments, shorten cab pressurizer filter intervals, and recheck tire pressure and wheel lean more frequently as ambient temperature swings affect blade control.
GD750A-1(S/N 7001-UP) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 1436 831 H1 | Filter, Air Recirculation - Rear | Air intake service | Check fitment → |
| 1266 752 H91 | Filter, All-Wheel Drive Hydraulic Oil | Hydraulic service | Check fitment → |
| 1214 275 H4 | Element, Hydraulic Oil Filter | Hydraulic service | Check fitment → |
| 1266 751 H2 | Element, Converter & Differential Oil Filter | Lubrication service | Check fitment → |
| 1438 960 H1 | Hose - From Hydraulic Filter Assembly | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
GD750A-1(S/N 7001-UP) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Engine oil pressure lamp (red) | Engine lubrication pressure has dropped below safe minimum | Low oil level, clogged oil filter/strainer, worn oil pump, or oil pressure sender fault | Stop engine immediately, check oil level and filter condition before restarting |
| Coolant temperature lamp (red) | Engine coolant temperature has exceeded normal operating range | Low coolant level, clogged radiator core, slipping or damaged fan drive, or faulty thermostat | Idle down, check coolant level and radiator/fan for debris once safe to inspect |
| Charge (alternator) lamp (red) | Charging circuit is not supplying current to the battery system | Broken or slipping alternator belt, failed alternator, or loose/corroded wiring connection | Check belt tension and battery terminals; test alternator output if lamp stays lit at running speed |
| Air cleaner restriction lamp (yellow) | Intake air filter restriction has reached the service limit | Dust-loaded primary air filter element or blocked pre-cleaner | Inspect and clean or replace the air filter element, reset the restriction indicator |
| Torque converter/transmission oil temperature lamp (red) | Power train oil temperature has exceeded the safe operating threshold | Low transmission oil level, clogged oil cooler, or sustained high-load/stall operation | Reduce load, let temperature drop, then check oil level and cooler for restriction |
| Parking brake indicator lamp | Parking brake is engaged or brake circuit pressure is low | Brake left applied, low hydraulic/air charge pressure to the brake release circuit, or a brake switch fault | Confirm parking brake lever position and check brake system charge pressure before moving the machine |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
GD750A-1(S/N 7001-UP) attachments & work tools
Moldboard (grading blade)
Standard moldboard is 4267 x 686 x 25 mm (14 ft x 27 in x 1 in) with 432 mm (17 in) arc radius, through-hardened cutting edge, and replaceable/reversible end bits. A 4877 mm (16 ft) x 27 in x 1 in moldboard with the same 17 in radius is factory optional for wider coverage. Optional cutting edges are also offered.
Blade positioning / circle system
Single-piece rolled-ring forged circle, 1816 mm (71.5 in) outside diameter, riding on six replaceable circle support shoes with 360 degree hydraulic rotation. Blade side shift is 737 mm (29 in) each direction, circle side shift 475 mm (18.7 in), max cutting depth 775 mm (30.5 in), max lift above ground 473 mm (18.6 in), and blade angle up to 90 degrees either way with 40 degree forward/5 degree backward tip range.
Rear ripper (scarifier)
Optional rear-mounted ripper with a holding valve, drawbar-mounted behind the tandem for breaking up hard or frozen material ahead of grading. Exact shank count and spacing for this serial range are not documented in the factory literature reviewed — verify with your dealer.
Pusher block
Optional front-mounted pusher block for light push/dozing duty and bumper protection. This is not a full dozer moldboard or snow wing — no dedicated front blade or snow-wing kit is listed as a factory option for this model.
Hydraulic shock accumulators
Optional anti-shock accumulators for the blade lift and circle side-shift circuits, cushioning hydraulic shock loads during heavy grading or ripping work.
Auxiliary hydraulic control valves
Standard hydraulic circuit uses a 9-station control valve bank with one spare station already wired in. Up to four additional control valve stations can be added as a factory option to run extra work-tool circuits.
Coupler / mounting hardware
Work tools mount through the standard drawbar-circle-moldboard assembly (A-shaped, U-section welded drawbar with replaceable drawbar ball) rather than a quick-coupler system; the rear ripper bolts to its own rear-mounted frame. An optional front-mounted tow hitch is available for towing separate implements.
Guarding and undercarriage options
Optional transmission guard protects the underside driveline. Optional tires beyond the standard 16.00x24-G2 12-ply tubeless tires are also offered, along with a standard toolbox for spare tools and edges.
All GD750A-1(S/N 7001-UP) assemblies by section
Every catalogued assembly group for the Komatsu GD750A-1(S/N 7001-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Brakes
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Brake Pedal
| 14***91 | Pedal, Brake | 1 |
| 14***H1 | Plate, Base | 1 |
| 14***H1 | Pedal | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Brake Valve
| 14***H1 | Boot | 1 |
| 14***91 | Valve, Brake | 1 |
| 14***91 | Kit, Brake Valve Seal | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Brakes
| 01***40 | Bolt,For Weight Adjusting Bolt | 12 |
| 01***45 | Bolt, Mounting Cranking Motor | 10 |
| 01***70 | Bolt - Accumulator Mounting Bracket | 24 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Hydraulic Brake Lines Brake Valve To Brakes
| 14***H1 | Coupling | 1 |
| 14***93 | Tube, Brake | 4 |
| 14***H1 | Hose | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Hydraulic Brake Lines Brake Valve To Priority Valve
| 14***H1 | Hose | 1 |
| 14***H1 | Hose | 1 |
| 14***H1 | Hose | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Parking Brake
| 01***30 | Bolt,(With Body Positioner) | 16 |
| 01***40 | Bolt,(For Slag Handling) (For Usa) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 16 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Parking Brake Caliper
| 14***91 | Caliper Assembly, Parking Brake | 1 |
| 14***H1 | Screw, Hex Socket Head Cap | 1 |
| 14***91 | Kits, Overhaul Parts | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Brakes : Parking Brake Hydraulic Lines
| 14***H1 | Hose | 1 |
| 16***47 | Coupling, Quick Disconnect | 1 |
| 16***44 | Cap, Dust | 1 |
Cooling
Komatsu : Gd750a-1(S/N 7001-Up) : Cooling : Converter Oil Cooler Lines
| 01***60 | Bolt,(With Body Positioner) | 1 |
| 14***92 | Transmission Cooling Lines | 0 |
| 14***H1 | O-Ring | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Cooling : Engine Fan And Shroud
| 01***25 | Bolt,(Rear Attachment Less) | 18 |
| 01***30 | Bolt,(With Body Positioner) | 4 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Cooling : Radiator And Oil Cooler
| 14***91 | Oil Cooler | 1 |
| 14***91 | Radiator | 1 |
| 73***36 | Cap, Radiator | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Cooling : Radiator Connections
| 14***H2 | Hose, Upper Radiator | 1 |
| 14***H2 | Hose, Lower Radiator | 1 |
| 14***44 | Valve, Shut-Off | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Cooling : Radiator Mounting
| 01***25 | Bolt,(Rear Attachment Less) | 23 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***40 | Bolt (Op) | 2 |
Drive Train
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : 1st Stage Shaft Transmission
| 12***H1 | Ring, Seal | 1 |
| 14***H1 | Ring, Seal | 1 |
| 14***92 | Shaft, 1st Stage | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : 6th Stage Shaft Transmission
| 14***92 | Shaft, 6th Stage | 1 |
| 14***H1 | Shaft, 6th Stage (32 Teeth) | 1 |
| 14***H1 | Gear, 6th Stage (39 Teeth) | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Charge Pump Transmission
| 14***H1 | Pump, Charge | 1 |
| 14***H1 | Screw, Set | 1 |
| 14***H1 | Bolt | 3 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Clutch Pack - 2nd Stage Transmission
| 12***H1 | Ring, Seal | 3 |
| 14***H1 | Shaft, 2nd Stage Assembly | 1 |
| 14***H1 | Seal, Piston Outer | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Clutch Pack - 3rd Stage Transmission
| 12***H1 | Ring, Seal | 2 |
| 14***H1 | Seal, Piston Outer | 1 |
| 14***H1 | Washer, Lube Shutoff | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Clutch Pack - 4th Stage Transmission
| 12***H1 | Ring, Seal | 3 |
| 14***H1 | Plate, Spring | 2 |
| 14***H1 | Spring, Bellville | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Clutch Pack - 5th Stage Transmission
| 12***H1 | Ring, Seal | 3 |
| 14***H1 | Seal, Piston Outer | 2 |
| 14***H1 | Washer, Lube Shutoff | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Differential Assembly Lock/Unlock
| 14***91 | Gear & Pinion, Ring | 1 |
| 14***H1 | Washer, Flat | 12 |
| 14***H1 | Bolt | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Differential Case Assembly
| 14***H1 | Plug | 3 |
| 14***91 | Case Assembly, Differential | 1 |
| 14***H1 | Tube, Breather | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Differential Input Housing
| 10***24 | Pin, Cotter | 1 |
| 14***91 | Seal, Lip | 1 |
| 14***H1 | Seal, V-Ring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Differential Oil Filter
| 01***30 | Bolt - Pin Mounting | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 12***H2 | Element, Converter & Differential Oil Filter | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Drive Line
| 01***35 | Bolt,(F4320-52a0 -5 ) | 12 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 1 |
| 01***45 | Bolt,(For 60ton Dump Body) | 6 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Drive Shaft
| 10***61 | Fitting, Grease | 1 |
| 14***92 | Shaft, Installation | 1 |
| 14***92 | Shaft, Drive | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Final Drive And Tandems With Planetary
| 01***50 | Bolt,(For D60pl) | 64 |
| 01***80 | Bolt,(For Large Size Tire) | 8 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 64 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Final Drive With Planetary
| 01***15 | Bolt | 8 |
| 01***60 | Bolt,For Weight Adjusting Bolt | 36 |
| 01***40 | Bolt | 28 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Front Cover Transmission
| 13***28 | Ring, Snap | 1 |
| 14***91 | Cover, Front Assembly | 1 |
| 14***H1 | Gear, Pulse (43 Teeth) | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Inching Pedal
| 01***23 | Washer,(With Auto Emergency Steering) | 3 |
| 14***91 | Pedal, Inching | 1 |
| 14***H1 | Sensor, Outline | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Input Housing Transmission
| 12***80 | Washer, Lock - Ground Screw | 2 |
| 14***H1 | Cover, Magnetic Sensor Pickup | 1 |
| 14***H1 | Housing, Input | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Lockup Converter Valve Transmission
| 14***H1 | Hanger, Lift | 1 |
| 14***H1 | Housing, Lockup Valve | 1 |
| 14***H1 | Sleeve, Bore | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Main Housing Transmission
| 12***80 | Washer, Lock - Ground Screw | 2 |
| 13***16 | Cup, Bearing | 1 |
| 14***H1 | Cover, Magnetic Sensor Pickup | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Main Regulator Transmission
| 12***H1 | Plate, Orifice | 1 |
| 12***H1 | Ring, Retaining | 1 |
| 13***77 | Washer | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Output Shaft Transmission
| 14***55 | O-Ring | 1 |
| 14***91 | Shaft, Output (71 Teeth) | 1 |
| 14***H1 | Retainer, Bearing | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Planetary Assembly
| 14***H1 | Gear, Ring | 1 |
| 14***H1 | Carrier, Planet | 1 |
| 14***H1 | Shaft, Pinion | 3 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Proportional Solenoid Valve Transmission
| 14***H1 | Coil, Solenoid - 24v | 1 |
| 14***91 | Valve, Proportional Solenoid - 24v | 1 |
| 14***H1 | Valve | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Tandem Drive With Planetary Final Drive
| 01***32 | Washer,(Not Used With Emergency Str.) | 16 |
| 11***C1 | Magnet | 1 |
| 14***H1 | Seal | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Torque Converter
| 12***H1 | Washer, Flat | 12 |
| 14***H1 | Impeller | 1 |
| 14***H1 | Turbine | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Transmission And Torque Converter
| 12***H1 | Fan, Blower - Engine | 12 |
| 12***H1 | Ring | 1 |
| 14***91 | Transmission & Torque Converter | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Transmission Control Valve Mounting Transmission
| 12***H1 | Washer, Flat | 27 |
| 14***H1 | Gasket | 1 |
| 14***H1 | Plate | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Transmission Control Valve Transmission
| 14***H1 | Valve, Relief | 1 |
| 14***H1 | Plug, Prop Solenoid | 1 |
| 14***H1 | O-Ring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Transmission Controls
| 01***70 | Bolt | 4 |
| 01***23 | Washer,(With Auto Emergency Steering) | 10 |
| 12***79 | Grommet | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Transmission Oil Filter
| 01***30 | Bolt - Pin Mounting | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 12***H4 | Element, Hydraulic Oil Filter | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Transmission Oil Filter Lines
| 14***H1 | Hose - In | 1 |
| 14***H1 | Hose - Out | 1 |
| 14***H1 | Hose - To Lube In Port On Transmission | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Drive Train : Yoke Transmission
| 14***H1 | Bolt | 1 |
| 14***H1 | Washer | 1 |
| 14***H1 | Seal, Ring | 1 |
Electrical
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Alternator - 50 Amp Model 20 Si
| 12***H1 | Bushing, Mounting Hinge | 1 |
| 12***H1 | Bolt, Field Coil And Support | 4 |
| 12***H1 | Bearing, Ball | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Alternator - 50 Amp Model 23 Si
| 12***H1 | Bearing, Ball | 1 |
| 12***H1 | Regulator And Resistor Assembly | 1 |
| 13***H1 | Rectifier Bridge Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Alternator - 80 Amp Model 30 Si
| 12***R1 | Washer, Lock - Ground Screw | 1 |
| 12***H1 | Bushing, Mounting Hinge | 1 |
| 12***H1 | Plug, Bearing Well | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Articulation Indicator
| 12***61 | Nut, Hex - No. 10-24 | 2 |
| 12***41 | Washer, Lock | 3 |
| 14***99 | Sending Unit, Articulation Indicator | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Battery And Connections
| 01***25 | Bolt,(Rear Attachment Less) | 2 |
| 01***54 | Bolt | 3 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Cranking Motor
| 12***38 | Nut, Terminal - C.E | 1 |
| 12***85 | Washer, Flat - At Field Coil | 1 |
| 12***96 | Washer, Terminal - C.E. Frame | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Cranking Motor Mounting
| 01***50 | Bolt,(For D60pl) | 3 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 3 |
| 14***92 | Cranking Motor | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Engine Wiring
| 01***25 | Capscrew | 2 |
| 01***25 | Bolt,(Rear Attachment Less) | 3 |
| 01***14 | Screw,(With Joy Stick Steering) | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Flashing Light Amber
| 12***H1 | Light, 360 Degrees - Flashing | 1 |
| 12***H1 | Connector | 1 |
| 14***H1 | Flasher, Turn Signal | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Front Bar Headlight Installation
| 01***20 | Bolt,(Without Air Con. Or Heater) | 6 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 4 |
| 01***23 | Washer,(With Auto Emergency Steering) | 6 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Horn
| 01***05 | Nut,(For Air Conditioner Less), Nut | 1 |
| 01***23 | Washer,(With Auto Emergency Steering) | 1 |
| 13***H1 | Horn | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Knock-Down Bracket Light Mount
| 10***96 | Adhesive, Rubber - 1 Qt. Can | 1 |
| 12***08 | Grommet | 1 |
| 13***55 | Pin, Cotter | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Lighting System
| 14***H1 | Grommet, Top Lights | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Rear Combination Lamp
| 01***35 | Screw, Mount Lens | 4 |
| 08***71 | Connector | 1 |
| 08***20 | Bulb? 25/10w,Tail And Stop Lamp | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Rear Wiring
| 01***25 | Capscrew | 4 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 6 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Sending Units
| 12***H1 | Sending Unit, Engine Water Temperature | 1 |
| 14***H2 | Switch, High Pressure | 1 |
| 14***H1 | Screw, Self-Tapping | 5 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Single Beam Halogen Lamp
| 12***H1 | Pin, Male | 2 |
| 12***H1 | Shroud, Female | 1 |
| 12***H1 | Seal, Terminal | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Steering Console Wiring
| 01***20 | Bolt,(Without Air Con. Or Heater) | 2 |
| 01***16 | Bolt - Seat And Tether Belt Mounting | 1 |
| 01***23 | Washer,(With Auto Emergency Steering) | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Strobe Light Amber
| 12***H2 | Light, Strobe | 1 |
| 12***H1 | Connector | 1 |
| 14***91 | Cable - From Light To Flasher | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Turn Signal Lamp
| 11***C1 | Connector, Male | 1 |
| 12***91 | Lamp, Turn Signal | 1 |
| 12***91 | Lamp Assembly, Turn Signal | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Electrical : Under Cab Wiring
| 01***05 | Nut,(For Air Conditioner Less), Nut | 5 |
| 01***23 | Washer,(With Auto Emergency Steering) | 5 |
| 12***93 | Washer, Flat | 2 |
Engine
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Accessories
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Cooling System
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Cylinder Block
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Cylinder Head
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Electrical System
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Engine Mounting
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Fuel System
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Gasket Sets And Repair Kits
Komatsu : Gd750a-1(S/N 7001-Up) : Engine : Lubricating Oil System
Frame
Komatsu : Gd750a-1(S/N 7001-Up) : Frame : Articulation Joint
| 01***60 | Bolt,For Weight Adjusting Bolt | 6 |
| 01***55 | Bolt,(Not Used For Chip Dozer) | 4 |
| 01***40 | Bolt,For Weight Adjusting Bolt | 8 |
Komatsu : Gd750a-1(S/N 7001-Up) : Frame : Main Frame
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 16 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***50 | Bolt,(For Large Size Tire) | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Frame : Transmission Guard
| 01***60 | Bolt,For Weight Adjusting Bolt | 8 |
| 01***10 | Nut,(Without Air Conditioner) | 8 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 8 |
Hydraulics
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Accumulator - Blade Cushion 4.75 In. X 16.19 In.
| 12***91 | Valve, Gas | 1 |
| 14***92 | Accumulator, Blade Lift Assembly | 1 |
| 14***H1 | Body | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Accumulator - Brake 3.56 In. X 18.94 In.
| 12***91 | Valve, Gas | 1 |
| 12***H1 | Protector, Gas Valve | 1 |
| 12***H1 | Screw | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Articulation Actuator Lines
| 14***H1 | Hose | 1 |
| 14***H1 | Hose | 1 |
| 14***H1 | Hose - To R.H. Articulation Cylinder | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Articulation Cylinder
| 07***06 | Bushing | 2 |
| 07***60 | Seal,(Y1620-41a0a-14) | 4 |
| 07***36 | Nut, Nylon | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Articulation Joint Clamp
| 01***32 | Washer,(With Auto Emergency Steering) | 8 |
| 12***H1 | Clamp, Hydraulic Hose | 2 |
| 12***H1 | Clamp, Hose - 3-Piece Set | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Auxiliary Control Levers
| 12***14 | Washer, Lock | 0 |
| 12***45 | Bearing, Teflon | 2 |
| 12***91 | Bearing | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Basic Hydraulics Pressure Lines
| 14***H1 | Bolt - Baffle To Front Frame | 4 |
| 14***91 | Connector | 1 |
| 14***H1 | Hose - From Steering Pump | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Basic Hydraulics Return Lines
| 14***H1 | Hose | 1 |
| 14***H1 | Hose | 1 |
| 14***H1 | Hose | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Basic Hydraulics Sensing Lines
| 14***H1 | Hose | 1 |
| 14***H1 | Hose - From Steering Pump | 1 |
| 14***H1 | Hose | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Lift Accumulator Assembly
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 8 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 8 |
| 14***91 | Blade Lift Accumulator Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Lift Actuator Lines
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***80 | Bolt | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Lift Cylinder
| 01***90 | Bolt | 2 |
| 01***18 | Nut | 2 |
| 01***60 | Washer,Single Flange (Trimming) | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Shift Actuator Lines
| 14***H1 | Sleeve, Hose Wrap - 44 In | 2 |
| 14***H2 | Hose - To Four-Way Swivel Valve | 1 |
| 14***H2 | Hose - To Four-Way Swivel Valve | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Side Shift Cylinder
| 07***08 | Plug,(For W/O. Corrosion Resistor) | 1 |
| 07***05 | Bushing | 2 |
| 07***50 | Seal,(Y1620-41a0a-3) | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Tilt Actuator Lines
| 14***H1 | Sleeve, Hose Wrap - 44 In | 2 |
| 14***H1 | Hose - To Four-Way Swivel Valve | 2 |
| 14***H1 | Hose - From Four-Way Swivel Valve | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Blade Tilt Cylinder
| 04***30 | Seal, Dust | 2 |
| 07***36 | Nut, Nylon | 1 |
| 07***62 | Ring, Snap | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Circle Reverse Actuator Lines
| 14***H1 | Sleeve, Hose Wrap - 44 In | 1 |
| 14***H1 | Hose | 2 |
| 93***C1 | Strap, Tie - Dual Hp Harness To Main Harness | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Circle Reverse Motor
| 14***91 | Motor, Circle Reverse | 1 |
| 14***H1 | Bolt, Special | 7 |
| 14***H1 | Cover, End | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Circle Shift Actuator Lines
| 14***H1 | Sleeve, Hose Wrap - 44 In | 3 |
| 14***H1 | Hose | 2 |
| 14***H1 | Hose | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Combination Holding/Float Valve
| 12***H1 | Kit, Seal | 1 |
| 14***91 | Valve, Combination Holding/Float | 1 |
| 14***91 | Cartridge, Counterbalance Valve | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve - L.H. Bank 5 Valves
| 10***26 | Nut, Regular Hexagon (3/8 - 24 Unf) | 2 |
| 14***91 | Kit, Tie Rod | 1 |
| 14***H1 | Shuttle | 5 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve - L.H. Bank 6 Valves
| 10***26 | Nut, Regular Hexagon (3/8 - 24 Unf) | 2 |
| 14***91 | Kit, Tie Rod | 1 |
| 14***H1 | Shuttle | 6 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve - R.H. Bank 4 Valves
| 10***26 | Nut, Regular Hexagon (3/8 - 24 Unf) | 2 |
| 14***91 | Cartridge, Main Relief Valve | 1 |
| 14***H1 | Shuttle | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve - R.H. Bank 5 Valves
| 10***26 | Nut, Regular Hexagon (3/8 - 24 Unf) | 2 |
| 14***91 | Kit, Tie Rod | 1 |
| 14***91 | Cartridge, Main Relief Valve | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve - R.H. Bank 6 Valves
| 10***26 | Nut, Regular Hexagon (3/8 - 24 Unf) | 2 |
| 14***91 | Kit, Tie Rod | 1 |
| 14***91 | Cartridge, Main Relief Valve | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve - R.H. Bank 7 Valves
| 10***26 | Nut, Regular Hexagon (3/8 - 24 Unf) | 2 |
| 14***91 | Kit, Tie Rod | 1 |
| 14***91 | Cartridge, Main Relief Valve | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve Mounting
| 01***40 | Bolt (Op) | 6 |
| 01***32 | Washer,(With Auto Emergency Steering) | 6 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Control Valve Outlet Section L.H. Bank
| 14***H1 | Spring | 1 |
| 14***H1 | Ring, Retaining | 1 |
| 14***H1 | Shuttle | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Differential Pump
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Drawbar Shift Cylinder
| 01***85 | Bolt | 4 |
| 01***18 | Nut | 4 |
| 01***60 | Washer,Single Flange (Trimming) | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Dual Counterbalance Valve Blade Tilt
| 14***91 | Cartridge, Relief Valve | 1 |
| 14***91 | Cartridge, Counterbalance Valve | 2 |
| 14***91 | Valve, Dual Counterbalance | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Dual Counterbalance Valve Circle Shift, Wheel Lean, Articulation
| 14***91 | Valve, Dual Counterbalance | 1 |
| 14***91 | Cartridge, Counterbalance Valve | 2 |
| 14***91 | Kit, Seal | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Dual Counterbalance Valve Ripper
| 14***91 | Valve, Dual Counterbalance | 1 |
| 14***91 | Cartridge, Counterbalance Valve | 2 |
| 14***91 | Kit, Seal | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Four-Way Swivel Block
| 12***H1 | Seal | 5 |
| 14***91 | Valve Body, Four-Way Swivel | 1 |
| 14***91 | Swivel Block, Four-Way | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Hydraulic Oil Filter
| 12***H4 | Element, Hydraulic Oil Filter | 1 |
| 12***91 | Base Assembly, Filter | 1 |
| 12***91 | Switch, Indicator | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Hydraulic Oil Tank
| 01***10 | Nut,(Without Air Conditioner) | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 9 |
| 11*** L | Elbow | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Hydraulic Pump
| 14***H2 | Hose, Suction - To Hydraulic Pump | 1 |
| 14***H1 | Hose - Hydraulic Pump Lube Line | 1 |
| 14***H1 | Hose - Steering/Brake Pump Lube Line | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Hydraulic System Pump
| 12***38 | Pin, Roll | 1 |
| 13***99 | Bearing, Needle | 1 |
| 13***03 | Bolt | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Hydraulic System Pump Compensator
| 14***H1 | Cover, Tamper Proof | 2 |
| 14***91 | Kit, Compensator Seal | 1 |
| 14***91 | Compensator Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Hydraulic System Pump Mounting
| 01***40 | Bolt,(For Slag Handling) (For Usa) | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 12***H1 | Sleeve, Pump Drive | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Lift Cylinder Cushion Valve
| 12***H1 | Nut, Coil | 1 |
| 14***92 | Valve, Lift Cylinder Cushion | 1 |
| 14***H1 | Coil | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Lock Pin Actuator Lines
| 14***H1 | Hose - To L.H. Cylinder | 1 |
| 14***H1 | Hose - To L.H. Cylinder | 1 |
| 14***H1 | Hose | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Lock Pin Cylinder
| 13***92 | Cylinder Assembly, Lock Pin | 2 |
| 13***91 | Cylinder Weldment | 1 |
| 13***92 | Piston Weldment | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Lock/Unlock Differential Control Valve
| 12***H1 | Kit, Seal | 1 |
| 14***92 | Valve, Directional Control | 1 |
| 14***91 | Kit, Seal | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Lock/Unlock Differential Hydraulic System
| 01***70 | Screw | 2 |
| 01***08 | Nut | 1 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Mounting - Steering/Brake & Differential Pumps
| 15***19 | O-Ring | 1 |
| 24***R1 | Bolt, 3/8nc X 1 - Mount Cleaner | 2 |
| 24***R1 | Bolt, Muffler To Bracket Mounting -1/2 Nc X 1 1/2 In | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Priority Valve
| 14***91 | Valve, Priority | 1 |
| 14***91 | Valve, Bypass Compensator Spool | 1 |
| 14***91 | Valve, Check | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Priority Valve To Return Valve Connection
| 01***45 | Bolt,(With Water Separator Type) | 8 |
| 01***32 | Washer,(With Auto Emergency Steering) | 8 |
| 14***H1 | Tube | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Return/Park Brake Combination Valve
| 12***H1 | Kit, Seal | 1 |
| 12***H1 | Nut, Coil | 1 |
| 12***H1 | Plug, Orifice - 0.052 In | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Ripper Control Lever Optional
| 12***14 | Washer, Lock | 1 |
| 12***45 | Bearing, Teflon | 2 |
| 12***H1 | Epoxy, General Purpose - 1.2 Oz | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Ripper Cylinder
| 07***07 | Bushing,Back-Up | 1 |
| 07***75 | Seal,Dust? Piston Rod | 2 |
| 07***47 | Nut, Nylon | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Ripper Cylinder Actuator Lines
| 01***45 | Screw | 3 |
| 14***H1 | Sleeve, Hose Wrap - 44 In | 3 |
| 14***H1 | Hose | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Steering & Brake Pump
| 12***H1 | Washer | 1 |
| 12***H1 | Washer, Thrust | 2 |
| 12***H1 | Bearing, Thrust | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Steering & Brake Pump Compensator
| 12***H1 | Plug Assembly | 2 |
| 14***91 | Kit, Compensator Seal | 1 |
| 14***H1 | Gasket, Compensator | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Steering Cylinder
| 07***26 | Nut, Nylon | 1 |
| 07***57 | Ring, Snap | 1 |
| 10***60 | Fitting, Grease | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Steering Cylinder Actuator Lines
| 14***H2 | Hose | 1 |
| 14***H2 | Hose | 1 |
| 14***H1 | Hose | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Steering Unit
| 14***92 | Unit, Steering | 1 |
| 14***H1 | Cap, End | 1 |
| 14***91 | Kit, Seal | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Articulation And Optional
| 13***01 | Screw, Socket Head | 2 |
| 14***H1 | Cap | 1 |
| 14***H1 | Spring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Circle Reverse
| 12***H1 | Spring | 1 |
| 13***01 | Screw, Socket Head | 2 |
| 14***H1 | Cap | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Drawbar Sideshift And Leaning Wheel
| 13***01 | Screw, Socket Head | 2 |
| 14***H1 | Cap | 1 |
| 14***H1 | Spring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Inlet
| 13***04 | Screw, Socket Head | 4 |
| 14***H1 | Plate, Seal | 2 |
| 14***H1 | Cap, Spool | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section L.H. Drawbar Lift
| 12***H1 | Spring | 1 |
| 14***H1 | Seat, Spring | 1 |
| 14***H1 | Spring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Moldboard Shift
| 12***H1 | Spring | 1 |
| 13***01 | Screw, Socket Head | 2 |
| 14***H1 | Cap | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Moldboard Tilt
| 13***01 | Screw, Socket Head | 2 |
| 14***H1 | Cap | 1 |
| 14***H1 | Spring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section R.H. Drawbar Lift
| 12***H1 | Spring | 1 |
| 14***H1 | Seat, Spring | 1 |
| 14***H1 | Spring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Valve Section Ripper
| 13***01 | Screw, Socket Head | 2 |
| 14***H1 | Cap | 1 |
| 14***H1 | Spring | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Wheel Lean Actuator Lines
| 14***H1 | Hose | 2 |
| 14***H2 | Hose | 1 |
| 14***H2 | Hose | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Hydraulics : Wheel Lean Cylinder
| 07***05 | Bushing | 1 |
| 07***50 | Seal,(Y1620-41a0a-3) | 2 |
| 07***55 | Seal,(Y1620-11a0a-3) | 2 |
Instruments
Komatsu : Gd750a-1(S/N 7001-Up) : Instruments : Console Switch Panel
| 01***20 | Screw, Machine | 6 |
| 01***30 | Screw | 4 |
| 12***22 | Nut-Hex Mach, 8-32 Znd 1 | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Instruments : Steering Console Instrument Panel
| 12***H2 | Gauge, Articulation | 1 |
| 14***H1 | Gauge, Converter Oil Temperature | 1 |
| 14***92 | Dash Assembly | 1 |
Miscellaneous
Komatsu : Gd750a-1(S/N 7001-Up) : Miscellaneous : External Decals Gd750a
| 09***00 | Komatsu | 1 |
| 09***10 | Plate? Mark,Komatsu (See Fig.U0150-Xxxx) | 2 |
| 11***C1 | Read Manuals | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Miscellaneous : Internal Decals Gd750a
| 12***59 | Tag, Caution | 1 |
| 14***H3 | Decal, Switch Panel | 1 |
| 14***H1 | Rivet | 1 |
Mounted Equipment
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : 1 Inch Moldboard
| 01***60 | Flat Washer - M20 (Hardened) | 40 |
| 07***15 | Plug, Cap | 8 |
| 12***H1 | Edge, Cutting - 3/4 In X 8 In X 7 Ft | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : Circle Reverse Gear
| 01***40 | Bolt,For Weight Adjusting Bolt | 4 |
| 01***90 | Bolt (Kit) | 8 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 8 |
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : Circle Reverse Gear Case With Slip Clutch
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***40 | Bolt (Op) | 8 |
| 01***10 | Capscrew | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : Drawbar And Circle With Wear Pads
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 6 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : Drawbar Lift
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 2 |
| 01***45 | Bolt, Mounting Cranking Motor | 8 |
| 01***50 | Bolt,(For D60pl) | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : Reversible Overlay End Bit
| 01***60 | Flat Washer - M20 (Hardened) | 12 |
| 14***91 | End Bit, Reversible Overlay | 1 |
| 14***91 | End Bit, Reversible Overlay | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Mounted Equipment : Ripper
| 01***45 | Bolt, Mounting Cranking Motor | 8 |
| 01***55 | Bolt - Mount Cage To Transmission Case | 2 |
| 01***70 | Capscrew - M24 | 14 |
Power
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Accelerator/Decelerator Control Linkage Hand Throttle
| 01***20 | Bolt,(Without Air Con. Or Heater) | 5 |
| 01***06 | Nut, (Service Parts) | 2 |
| 01***23 | Washer,(With Auto Emergency Steering) | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Accelerator/Decelerator Control Linkage Pedal To Injection Pump
| 01***25 | Bolt,(Rear Attachment Less) | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***06 | Nut | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Accelerator/Decelerator Pedal
| 01***20 | Bolt,(Without Air Con. Or Heater) | 4 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 1 |
| 01***23 | Washer,(With Auto Emergency Steering) | 3 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Air Cleaner
| 12***H1 | Nut, Wing - Air Cleaner Cover | 1 |
| 12***H1 | Retainer | 1 |
| 12***H1 | Gasket, End Cover | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Air Intake System
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***80 | Bolt,(With Corrosion Resistor) | 1 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 5 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Ether Injection Starting Aid
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 2 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Exhaust System
| 01***16 | Bolt - Box Mounting | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
| 01***30 | Bolt,(With Body Positioner) | 6 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Fuel Lines
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 1 |
| 01***25 | Bolt, Pinlock | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Power : Fuel Tank
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 8 |
| 01***10 | Nut,(Without Air Conditioner) | 8 |
Steering
Komatsu : Gd750a-1(S/N 7001-Up) : Steering : Steering Column
| 12***91 | Column, Steering | 1 |
| 13***44 | Cap, Outer Tube | 1 |
| 14***H1 | Kit, Horn Brush Replacement | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Steering : Steering Console
| 01***20 | Bolt,(Without Air Con. Or Heater) | 8 |
| 01***16 | Bolt - Seat And Tether Belt Mounting | 1 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Steering : Steering Console Control Levers Standard
| 01***25 | Capscrew | 8 |
| 01***23 | Washer,(With Auto Emergency Steering) | 8 |
| 10***96 | Adhesive, Rubber - 1 Qt. Can | 0 |
Komatsu : Gd750a-1(S/N 7001-Up) : Steering : Steering Control Assembly
| 01***30 | Bolt,(With Body Positioner) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 14***92 | Bracket Weldment, Steering Mounting - L.H | 1 |
Superstructure
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Air Conditioner Compressor Mounting
| 11***91 | Kit, Hardware | 1 |
| 14***91 | Compressor, Air Conditioner | 1 |
| 14***91 | Clutch, Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Air Conditioner Lines
| 01***30 | Bolt - M8 X 30lg | 7 |
| 01***20 | Bolt,(For Mono Lever Steering) | 3 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 3 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Air Conditioner/Heater Box Assembly Evaporator
| 14***H1 | Switch, Ac/Heater Master | 1 |
| 14***H1 | Switch, Rocker Master | 1 |
| 14***H1 | Washer, Lock | 3 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Air Recirculation Valve Assembly - L.H.
| 12***75 | Nut - Mounting | 1 |
| 12***H1 | Washer, Nylon | 2 |
| 14***H1 | Panel, Flapper Bracket | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Air Recirculation Valve Assembly - R.H.
| 12***75 | Nut - Mounting | 1 |
| 12***H1 | Washer, Nylon | 2 |
| 14***H1 | Panel, Flapper Bracket | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Battery Box
| 01***20 | Bolt,(For Mono Lever Steering) | 12 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 8 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Blower Assembly
| 12***H1 | Gasket, Motor Mounting | 1 |
| 14***H1 | Clip, Blower Wheel | 1 |
| 14***H1 | Motor Assembly, Blower | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Assembly
| 10***96 | Adhesive, Rubber - 1 Qt. Can | 0 |
| 11***C1 | Bolt, Latch | 0 |
| 11***75 | Grommet | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Dome Light
| 12***H1 | Bulb, Dome Light | 2 |
| 13***14 | Washer, Flat | 8 |
| 13***44 | Washer, Lock | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Door Left Hand
| 12***75 | Nut - Mounting | 3 |
| 12***H1 | Washer, Nylon | 1 |
| 12***H1 | Rotary Latch Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Door Right Hand
| 12***75 | Nut - Mounting | 3 |
| 12***H1 | Washer, Nylon | 1 |
| 12***H1 | Rotary Latch Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Glass
| 13***H1 | Seal | 5 |
| 14***H1 | Glass, Side | 2 |
| 14***H1 | Silicone | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Group
| 14***91 | Cab Installation | 1 |
| 14***91 | Air Exchanger Box Assembly | 2 |
| 14***H1 | Seal | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Mounting
| 11***34 | Washer, Special - Rops | 2 |
| 11***85 | Mount, Rubber | 4 |
| 14***H1 | Spacer | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Panel Filter Assembly
| 12***H1 | Filter, Cab Vent | 1 |
| 12***H1 | Gasket, Filter Mounting | 2 |
| 14***21 | Seal | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Cab Steps
| 01***45 | Bolt,(With Water Separator Type) | 24 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***09 | Nut, Lock | 24 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Defroster Fan Front And Rear
| 11***C1 | Washer, Flat | 4 |
| 11***C1 | Motor, Fan | 1 |
| 12***91 | Washer, Plain | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Defroster Fan Mounting
| 12***92 | Washer, Flat - 0.25 | 4 |
| 14***91 | Defroster Fan | 1 |
| 14***91 | Defroster Fan | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Floor Mats
| 14***H1 | Mat - Top | 1 |
| 14***H1 | Mat - Bottom | 1 |
| 14***91 | Retainer, Floormat - R.H | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Glovebox
| 14***H1 | Glovebox | 1 |
| 14***H1 | Door, Glovebox | 2 |
| 14***91 | Glovebox Assembly | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Heater Box Assembly
| 14***H1 | Plate Weldment, Control | 1 |
| 14***H1 | Switch, Rocker Master | 1 |
| 14***H1 | Washer, Lock | 3 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Heater Hose
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 1 |
| 10***99 | Stud, Weld | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Hinged Lower Front Window
| 11***C1 | Grommet, Rubber | 4 |
| 12***H1 | Shim, Rubber | 2 |
| 12***H1 | Glazing | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Hood Side
| 01***16 | Bolt - Box Mounting | 8 |
| 01***12 | Bolt - M8 - 1.25 X 12 | 8 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 8 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Hood Top
| 01***20 | Bolt,(For Mono Lever Steering) | 9 |
| 01***32 | Washer,(With Auto Emergency Steering) | 9 |
| 14***91 | Hood Weldment | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Inside Rear-View Mirror
| 11***C1 | Mirror, Convex | 1 |
| 12***96 | Washer, Terminal - C.E. Frame | 2 |
| 14***91 | Mount, Mirror | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Lower Front Hinged Window Assembly
| 01***20 | Bolt,(Without Air Con. Or Heater) | 8 |
| 01***20 | Screw | 16 |
| 01***16 | Screw | 4 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Mirror Mounting West Coast
| 12***77 | Nut, Mounting - 3/8-16 Hex | 4 |
| 12***H1 | Head, Mirror | 2 |
| 12***H1 | Arm, Bow | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Platform Assembly
| 01***20 | Bolt,(Without Air Con. Or Heater) | 45 |
| 01***16 | Screw | 8 |
| 01***30 | Screw | 8 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Suspension Seat Gray Pvc
| 14***H1 | Height Riser Latch Assembly | 1 |
| 14***91 | Kit, Handles | 1 |
| 14***91 | Kit, Suspension Cover | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Suspension Seat Gray Rib Fabric/Gray Pvc
| 14***H1 | Height Riser Latch Assembly | 1 |
| 14***91 | Kit, Handles | 1 |
| 14***91 | Kit, Suspension Cover | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Trim Group
| 01***20 | Bolt,(For Mono Lever Steering) | 5 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***50 | Bolt,(Spark Arrester Spec.) | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Window Washer
| 01***12 | Bolt - M8 - 1.25 X 12 | 4 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 4 |
| 12***H1 | Pump, Windshield Washer | 2 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Windshield Wiper Assembly Lower Front
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Windshield Wiper Front Upper And Rear
| 14***91 | Blade, Wiper - 20 In | 1 |
| 14***91 | Arm, Wiper - 16 In. - Washer Option | 2 |
| 14***91 | Blade, Wiper - 18 In | 1 |
Komatsu : Gd750a-1(S/N 7001-Up) : Superstructure : Windshield Wiper Motor Front Upper And Rear
| 14***91 | Motor Assembly, Windshield Wiper | 2 |
| 14***H1 | Washer, Flat | 1 |
| 14***H1 | Washer, Flat | 1 |
Suspension
Komatsu : Gd750a-1(S/N 7001-Up) : Suspension : Front Axle
| 01***20 | Bolt,(For Mono Lever Steering) | 8 |
| 01***35 | Bolt,(With Rops) | 4 |
| 01***40 | Bolt,(For Slag Handling) (For Usa) | 6 |
Wheels And Traction
Komatsu : Gd750a-1(S/N 7001-Up) : Wheels And Traction : Wheels And Rims
| 01***10 | Washer | 12 |
| 01***00 | Bolt,L.H | 60 |
| 01***80 | Washer,(For R.H. Steering) | 60 |
GD750A-1(S/N 7001-UP) serial number reference
The PIN/serial plate on a GD750A-1 grader is mounted on the machine frame, typically near the front frame or articulation area on the right side as seen facing the direction of travel, and is also stamped on the equipment nameplate riveted to the frame. This model uses Komatsu's older plain numeric serial numbering (no 3-letter PIN prefix), so the plate shows a numeric serial that falls within the 7001-and-up range for this model.
| Prefix | Identifies | Notes |
|---|---|---|
| 7001 | GD750A-1 base production run (S/N 7001-UP) | Only serial break documented for this model designation across shop and parts manual listings; no alpha or configuration sub-prefixes found for this range. Turbocharged Cummins M11-C diesel (approx. 168 kW / 225 hp) tied to this range. Some equipment listings cite the cutoff as 7003-and-up instead of 7001-and-up for the same model name — treat as a minor documented discrepancy and confirm the exact cutoff with a Komatsu dealer for a specific unit. |
Frequently asked questions
What engine powers the Komatsu GD750A-1 (S/N 7001-UP)?
A Cummins M11-C six-cylinder turbocharged diesel of 10.8 L displacement with a mechanical PT-governed fuel system (no engine ECM), rated 183 kW (245 HP) gross and 168 kW (225 HP) net at 2000 rpm.
What is the operating weight of the GD750A-1?
Approximately 19,050 kg (42,000 lb) as a four-wheel-drive machine with the standard 4267 mm (14 ft) moldboard, full fluids, and operator.
What replaced the Komatsu GD750A-1?
No direct successor model is documented for this exact serial range (S/N 7001-UP). Komatsu's large motor grader lineup moved on to other model designations in later years, but a confirmed model-for-model replacement is not established in available factory documentation.
What GD750A-1(S/N 7001-UP) owners discuss
What do operators and mechanics say about the Cummins M11-C engine in the GD750A-1?
Consensus from vocational-truck and off-road mechanics who have worked on M11-C/CELECT engines (the same electronic control generation used in this grader) is that the block itself is regarded as tough and long-lived, but the early electronic controls are the weak point. A common complaint is hard starting after the machine sits: a one-way check valve on the ECM cooling plate is supposed to keep the fuel filter and lines primed, and when it fails fuel drains back overnight, causing long crank times. A weak engine position sensor is another recurring cause of extended cranking, since it struggles to give a clean signal for injector timing at low cranking RPM. On the electronic side, a boost-pressure-sensor fault reading physically impossible pressure will trigger an automatic derate to a low-boost limp mode, which owners often first notice as a sudden loss of power rather than a warning light. None of these are unique to the grader application, but heat, dust, and vibration in off-road duty are cited as accelerating factors versus highway use.
What hydraulic problems come up most often on this generation of Komatsu grader?
The two areas mechanics flag most are circle turn/blade lift response and the front wheel lean circuit. Sluggish or jerky circle and blade lift movement is usually traced to low or contaminated hydraulic fluid, a worn control valve, or a relief valve that has drifted out of spec rather than pump failure outright. On the front wheel lean cylinders, gradual drift or lean angle loss when the machine sits overnight points to internal seal bypass; the standard diagnostic is to pressure-test each cylinder side independently rather than assume the pump or steering valve is at fault. Loss of steering pressure entirely is more often a clogged filter or a failed relief valve than a pump replacement job. Because wheel lean and steering affect grading accuracy and machine control, have your dealer verify any diagnosis before returning the machine to service.
What wear pattern is typical for the circle and drive components on this class of grader?
The circle drive is the highest-wear assembly on any motor grader of this size, and the community-consensus maintenance habit is to grease the circle drive pinion and circle teeth after every full shift to keep abrasive grit from packing into the mesh. A distinction mechanics stress is that the circle's top and interior wear surfaces are meant to run on a dry-film lubricant, not grease, while the pinion and ring teeth need conventional grease; using the wrong lubricant type in the wrong location is a repeat cause of premature wear complaints. Contact stress at the pinion-to-ring interface is high enough that inadequate lubrication or missed greasing intervals shows up as metal deformation and backlash within a season or two of heavy grading work, requiring shoe/shim adjustment to bring backlash back into spec.
Are there known electrical or sensor issues specific to this era of Komatsu grader?
Since the GD750A-1(S/N 7001-UP) uses the CELECT-generation Cummins electronic control system rather than a modern CAN-based ECM, the electrical quirks reported are mostly tied to that control era: dropped ECM power during cranking (which can prevent some fault codes from logging at all, making a no-start look like "no codes found"), and sensor-driven derates from boost or coolant temperature circuits rather than fuel system faults. Wiring harness chafe and corroded connectors are cited as the most common root cause of intermittent no-codes issues on this control generation, more often than component failure. Owners should not expect modern self-diagnostic depth from this machine; a fault code reader compatible with the older CELECT protocol is needed, and hookup and diagnosis should be handled or verified by a dealer technician familiar with the era.
How does the GD750A-1 compare to Caterpillar graders in operator feedback?
Where operators moving between brands comment on Komatsu graders of this size class, the most repeated observation is ergonomic rather than mechanical: the control levers are set slightly larger and further apart than on comparable Caterpillar graders, which some operators note as a short adjustment period rather than a flaw. Separately, forum discussion of Komatsu heavy equipment generally (not this model specifically) sometimes raises concerns about parts support and resale value compared to Caterpillar or John Deere in a given region; this varies heavily by dealer network and geography rather than being a fixed brand issue, so it is worth checking local parts and service support before purchase rather than relying on general forum sentiment.
What should a buyer check on a used GD750A-1(S/N 7001-UP)?
Beyond the general fluid and leak inspection any used grader gets (clean, correct-level engine oil, coolant, and hydraulic fluid; no active leaks at cylinders, hoses, or fittings), buyers should specifically test the front wheel lean cylinders for overnight drift, cycle the circle through full turn travel checking for backlash or binding, and ask for the circle greasing and shim-adjustment history since this is the highest-wear assembly on the machine. Given the CELECT-era Cummins controls, pull stored and active fault codes with a compatible reader rather than relying on the absence of a dash warning light, since some fault conditions on this control generation do not reliably log. Inspect moldboard, cutting edge, and tire wear for signs of consistent one-sided grading load, and check the drawbar and articulation joints for play. Because engine derate faults, steering response, and circle integrity are all safety-relevant to grading control, have your dealer verify engine fault history and hydraulic cylinder condition before final purchase.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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