Machine models

Komatsu HM300-2 and HM400-3M0 specifications

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Listing-entry count
2

Short answer

Komatsu HM300-2 and HM400-3M0: articulated dump trucks.

Selected configuration figures
Configuration	Documented field and quantity
HM300-2	Gross Power 340 hp Overall Length 34.26 ft
HM400-3M0	Gross Power 453 hp Overall Length 36.44 ft

HM300-2 and HM400-3M0 specification matrix — Listing labels reported by the source
Publisher name	Source guide	Listing-entry count	Labels named by the source
Komatsu	HM300-2 and HM400-3M0	2	HM300-2 and HM400-3M0

Dimensions and weight
Specification	HM300-2	HM400-3M0
Overall Length	34.26 ft	36.44 ft
Overall Width	9.52 ft	11.32 ft
Overall Height	11.55 ft	12.26 ft
Ground Clearance	1.68 ft	2.33 ft
Turning Radius – Outside Minimum	26.09 ft	28.88 ft
Tyre Gauge	7.49 ft	9.72 ft

Steering System
Specification	HM300-2	HM400-3M0
Steering System Type	Articulated type, fully hydraulic power steering with two double-acting cylinders	Articulated type, fully hydraulic power steering with two double acting cylinders
Supplementary Steering	Automatically actuated electrically powered	Automatically actuated electrically powered
Minimum Turning Radius, Wall To Wal	7.96 m 26\'1\"	8.80 m
Articulation Angle	45°each direction	45°each direction

Specification	HM400-3M0
Standard	ISO5010, SAE J1511

Electrical System
Specification	HM300-2	HM400-3M0
Alternator	24V, 75 Ah	24V, 75 Ah
Batteries	12V, 136 Ah x 2	12V, 136 Ah x 2
Starter Motor	24V, 11.0 kW	24V, 11.0 kW

Suspension System
Specification	HM300-2	HM400-3M0
Rear	Combined hydro-pneumatic and rubber suspension system	Combined hydro-pneumatic and rubber suspension system
Front	Hydro-pneumatic suspension	Hydro-pneumatic suspension

Main Frame
Specification	HM300-2	HM400-3M0
Main Frame Type	Articulated type, box-sectioned construction on front and rear Connected by strong torque tubes	Articulated type, box-sectioned construction on front and rear Connected by strong torque tubes

Body
Specification	HM300-2	HM400-3M0
Capacity Struck	16.9 yd3	23.9 yd3
Heaped (2:1, SAE)	21.7 yd3	31.4 yd3
Payload	27.3 metric tons 30.1 US tons	40.0 metric tons
Material	130 kg/mm2 184,925 psi high tensile strength steel	130 kg/mm2 high tensile strength steel
Material Thickness-Bottom	0.6 in	0.6 in
Material Thickness-Front	0.4 in	0.4 in
Material Thickness-Sides	0.5 in	0.5 in
Target Area	5,240 mm x 2685 mm 17\'2\" x 8\'10\"	5,667 mm x 3194 mm
Heating	Exhaust heating (option)	Exhaust heating (option)

Engine
Specification	HM300-2	HM400-3M0
Number Of Cylinders	6	6
Engine Model	Komatsu SAA6D125E-5	Komatsu SAA6D140E-5
Engine Type	Water-cooled, 4-cycle	Water-cooled, 4-cycle
Gross Power	340 hp	453 hp
Lubrication	Method- Gear pump, force-lubrication Filter-Full-flow type	Method- Gear pump, force-lubrication Filter-Full-flow type
Air Cleaner	Dry type with double elements and precleaner (cyclonpack type), plus dust indicator EPA Tier 3 and EU Stage 3A emissions certified	Dry type with double elements and precleaner, plus dust indicator *Net horsepower at the maximum speed of radiator cooling fan is 307 kW 411 HP EPA Tier 3 and EU Stage 3A emissions certified
Governor	Electronically controlled	Electronically controlled
Net Power	329 hp	448 hp
Power Measured @	2,000 rpm	2,000 rpm
Aspiration	Turbo-charged, after-cooled, cooled EGR	Turbo-charged, after-cooled, cooled EGR
Displacement	674 cu in	930.1 cu in
Bore	5 in	5.6 in
Stroke	6 in	6.5 in
Fan Drive Type	Mechanical	Hydraulic
Fuel System	Direct injection	Direct injection
Maximum Torque	174 kg•m 1,259 lb ft	Gross 2089 N•m 213 kg•m

Capacities
Specification	HM300-2	HM400-3M0
Fuel Tank - Diesel	101.5 gal	136.9 gal
Final Drive	6.3 gal	8.5 gal
Hydraulic System	31.7 gal	44.2 gal
Engine Oil	9.8 gal	13.3 gal
Torque Converter, Transmission And Retarder Cooling	20.5 gal	33.1 gal
Differentials	16.8 gal	28.6 gal
Suspension	2.7 gal	5.4 gal

Transmission and speeds
Specification	HM300-2	HM400-3M0
Travel Speed	36.4 mph	34.8 mph
Torque Converter	3-elements, 1-stage, 2-phase	3-elements, 1-stage, 2-phase
Transmission	Full-automatic, counter-shaft type	Full-automatic, counter-shaft type
Speed Range	6 speeds forward and 2 reverse	6 speeds forward and 2 reverse
Lockup Clutch	Wet, single-disk clutch	Wet, single-disk clutch
Forward	Torque converter drive in 1st gear, direct drive in 1st lockup and all higher gears	Torque converter drive in 1st gear, direct drive in 1st lockup and all higher gears
Reverse	Torque converter drive and direct drive in all gear	Torque converter drive and direct drive in all gear
Shift Control	Electronic shift control with automatic clutch modulation in all gear	Electronic shift control with automatic clutch modulation in all gear

Weights
Specification	HM300-2	HM400-3M0
Gross Weight	113,360 lb	163,418 lb
Empty Weight	53,000 lb	75,056 lb
Front Axle - Empty	55.8 %	56.9 %
Center Axle - Empty	23.6 %	23.1 %
Rear Axle - Empty	20.6 %	20 %
Front Axle - Loaded	30.3 %	29.4 %
Center Axle - Loaded	35.5 %	35.4 %
Rear Axle - Loaded	34.2 %	35.2 %

Tires
Specification	HM300-2	HM400-3M0
Standard Tire	23.5 R25	29.5 R25

Axles
Specification	HM300-2	HM400-3M0
Differential	3.154	3.727
Planetary	4.667	4.941

Hydraulic System
Specification	HM300-2	HM400-3M0
Hoist Cylinder	Twin, 2-stage telescopic type	Twin, telescopic type
Relief Pressure	20.6 MPa 210 kg/cm2 2,990 psi	28.4 MPa 290 kg/cm2 Hoist time
Hoist Time	12 sec	12 sec

Cab
Specification	HM300-2	HM400-3M0
Compliance	Dimensions comply with ISO 3471 ROPS (Roll-Over Protective Structure) standard	Comply with ISO 3471 ROPS (Roll-Over Protective Structure) standard, and ISO 3449 FOPS (Falling Objects Protective Structure : Level II)Standard

Brakes
Specification	HM300-2	HM400-3M0
Service Brake	Full-hydraulic control, oil-cooled multiple-disc type on front and center axles	Full Hydraulic control, oil cooled , multiple disc type on front and centre axles
Parking Brake	Spring applied, caliper disc type	Spring applied, caliper disc type
Retarder	Front and center axle brakes act as retarder	Front and center axle brakes act as retarder

Specification	HM400-3M0
Standard	ISO3450

Variants — Source comparison annotation
Source guide	Differing-field count reported
HM300-2 and HM400-3M0	47

Ratios
Figure	HM300-2	HM400-3M0
Engine horsepower per 1,000 lb of weight	6.2	6.0

HM300-2 and HM400-3M0: owner reports

Related account: “Stuck in low gear, controller errors and transmission rebuild effort”: Hm300-1 to HM400-2.

History and service record of HM300-2 and HM400-3M0

HM400-3M0 design goals. Trade Earthmovers reported that the HM400-3M0 was designed to raise productivity and cut costs through an advanced traction and transmission system, a higher dump body capacity and lower fuel consumption. Komatsu articulated dump truck breaks new ground, Trade Earthmovers.
Payload over the HM400-2. Komatsu Australia's Richard Feehely said an optimised body design pushed the HM400-3M0's payload to a true 40 metric tonnes, against 36.5 tonnes on the HM400-2, and that its 3,164 mm loading height matches 36- to 55-tonne excavators or 4.2 to 5.7 cubic metre wheel loaders. Komatsu articulated dump truck breaks new ground, Trade Earthmovers.
Retarder and payload meter. The HM400-3M0 has a 510 kW retarder so the operator can hold a chosen speed downhill with a full load, and a factory-fitted payload meter that lets production and working conditions be analysed on a computer. Komatsu articulated dump truck breaks new ground, Trade Earthmovers.
Later low-emission versions. Komatsu said it introduced the HM400-3M0 in Australia in 2014 and later released the HM300-5 and HM400-5 with Tier 4 final engines, keeping the exclusive hydraulic braking and retarder system that gives control downhill when fully loaded. Komatsu launches low-emission high-tech articulated dump trucks, Trucksales.

HM300-2 and HM400-3M0: forum references — Forum-title search
Forum index	Equipment class queried	Names in the search	Matching titles
Heavy Equipment Forums	articulated dump truck	Komatsu and the HM400 line that the HM300-2, HM400-3M0 belongs to (no title names the exact model). That is too few titles to say what owners mostly ask about, so the most recent are listed instead	8

Komatsu Hm 300 2 Articulated Truck With Codes (Heavy Equipment Forums, 2026-07-30)
Komatsu Hm400 (Heavy Equipment Forums, 2025-09-03)
Komatsu Artic Hm 400 (Heavy Equipment Forums, 2021-02-04)
Komatsu Hm300 2 (Heavy Equipment Forums, 2017-05-31)

Used market for the HM300-2 and HM400-3M0 — Dated first-page listing snapshot
Observation date	Listing source	Equipment search	Listings
2026-09-24	MachineryTrader	Komatsu articulated dump truck	21

Model	Listed	Model years	Lowest asking	Highest asking	Median asking	Median hours
HM300-2	19	2006 to 2017	$35,096	$223,347	$81,482	13,000
HM400-3M0	2	2019 to 2024	$337,776	$337,776	$337,776	1,255

HM300-2 and HM400-3M0: recall reference — Dated CPSC search
Search date	Database	Names queried	Search result
2026-09-24	U.S. Consumer Product Safety Commission	Komatsu together with the articulated dump truck HM300-2, HM400-3M0	No matching recall in this search

Sources for this page
Evidence class	Document, classification and recorded date
Reference site	Reference site: Komatsu HM300-2 — RitchieSpecs. Observed 2026-09-24.
Reference site	Reference site: Komatsu HM400-3M0 — RitchieSpecs. Observed 2026-09-24.
Forum threads	Forum threads: Heavy Equipment Forums thread index for Komatsu HM300-2 and HM400-3M0 — Heavy Equipment Forums. Observed 2026-09-24.
Published history	Published history Source: Komatsu articulated dump truck breaks new ground, Trade Earthmovers — Com. Observed 2026-09-30.
Published history	Published history Source: Komatsu launches low-emission high-tech articulated dump trucks, Trucksales — Com. Observed 2026-09-30.
Used-market listings	Used-market listings: MachineryTrader listings for Komatsu HM300-2 — MachineryTrader. Observed 2026-09-24.
Federal agency data	Federal agency data: Recall database search for Komatsu — U.S. Consumer Product Safety Commission. Observed 2026-09-24.

Recorded observations — Forum-title snapshot
Observation field	Recorded value
Title count	8
Forum indexes	Heavy Equipment Forums
Search wording	the HM300-2 and HM400-3M0 articulated dump truck
Latest title quoted by the reference	Komatsu Hm 300 2 Articulated Truck With Codes

Komatsu HM300-2 and HM400-3M0: Configuration records

HM300-2

Specification	Source figure
Dimensions and weight
Overall Length	34.26 ft
Overall Width	9.52 ft
Overall Height	11.55 ft
Ground Clearance	1.68 ft
Turning Radius – Outside Minimum	26.09 ft
Tyre Gauge	7.49 ft
Engine
Number Of Cylinders	6
Engine Model	Komatsu SAA6D125E-5
Gross Power	340 hp
Net Power	329 hp
Power Measured @	2,000 rpm
Displacement	674 cu in
Aspiration	Turbo-charged, after-cooled, cooled EGR
Bore	5 in
Stroke	6 in
Engine Type	Water-cooled, 4-cycle
Lubrication	Method- Gear pump, force-lubrication Filter-Full-flow type
Air Cleaner	Dry type with double elements and precleaner (cyclonpack type), plus dust indicator EPA Tier 3 and EU Stage 3A emissions certified
Governor	Electronically controlled
Fan Drive Type	Mechanical
Fuel System	Direct injection
Maximum Torque	174 kg•m 1,259 lb ft
Transmission and speeds
Travel Speed	36.4 mph
Torque Converter	3-elements, 1-stage, 2-phase
Transmission	Full-automatic, counter-shaft type
Speed Range	6 speeds forward and 2 reverse
Lockup Clutch	Wet, single-disk clutch
Forward	Torque converter drive in 1st gear, direct drive in 1st lockup and all higher gears
Reverse	Torque converter drive and direct drive in all gear
Shift Control	Electronic shift control with automatic clutch modulation in all gear
Weights
Front Axle - Empty	55.8 %
Rear Axle - Empty	20.6 %
Front Axle - Loaded	30.3 %
Rear Axle - Loaded	34.2 %
Center Axle - Empty	23.6 %
Center Axle - Loaded	35.5 %
Gross Weight	113,360 lb
Empty Weight	53,000 lb
Steering System
Steering System Type	Articulated type, fully hydraulic power steering with two double-acting cylinders
Supplementary Steering	Automatically actuated electrically powered
Minimum Turning Radius, Wall To Wal	7.96 m 26'1"
Articulation Angle	45°each direction
Electrical System
Alternator	24V, 75 Ah
Batteries	12V, 136 Ah x 2
Starter Motor	24V, 11.0 kW
Suspension System
Rear	Combined hydro-pneumatic and rubber suspension system
Front	Hydro-pneumatic suspension
Main Frame
Main Frame Type	Articulated type, box-sectioned construction on front and rear Connected by strong torque tubes
Body
Capacity Struck	16.9 yd3
Heaped (2:1, SAE)	21.7 yd3
Payload	27.3 metric tons 30.1 US tons
Material	130 kg/mm2 184,925 psi high tensile strength steel
Material Thickness-Bottom	0.6 in
Material Thickness-Front	0.4 in
Material Thickness-Sides	0.5 in
Target Area	5,240 mm x 2685 mm 17'2" x 8'10"
Heating	Exhaust heating (option)
Capacities
Fuel Tank - Diesel	101.5 gal
Final Drive	6.3 gal
Engine Oil	9.8 gal
Torque Converter, Transmission And Retarder Cooling	20.5 gal
Differentials	16.8 gal
Suspension	2.7 gal
Tires
Standard Tire	23.5 R25
Axles
Differential	3.154
Planetary	4.667
Hydraulic System
Hoist Cylinder	Twin, 2-stage telescopic type
Hoist Time	12 sec
Relief Pressure	20.6 MPa 210 kg/cm2 2,990 psi
Cab
Compliance	Dimensions comply with ISO 3471 ROPS (Roll-Over Protective Structure) standard
Brakes
Service Brake	Full-hydraulic control, oil-cooled multiple-disc type on front and center axles
Parking Brake	Spring applied, caliper disc type
Retarder	Front and center axle brakes act as retarder
Additional specifications
Hydraulic System	31.7 gal

Source

HM400-3M0

Specification	Source figure
Dimensions and weight
Overall Length	36.44 ft
Overall Width	11.32 ft
Overall Height	12.26 ft
Ground Clearance	2.33 ft
Turning Radius – Outside Minimum	28.88 ft
Tyre Gauge	9.72 ft
Engine
Number Of Cylinders	6
Engine Model	Komatsu SAA6D140E-5
Gross Power	453 hp
Net Power	448 hp
Power Measured @	2,000 rpm
Displacement	930.1 cu in
Aspiration	Turbo-charged, after-cooled, cooled EGR
Bore	5.6 in
Stroke	6.5 in
Engine Type	Water-cooled, 4-cycle
Lubrication	Method- Gear pump, force-lubrication Filter-Full-flow type
Air Cleaner	Dry type with double elements and precleaner, plus dust indicator *Net horsepower at the maximum speed of radiator cooling fan is 307 kW 411 HP EPA Tier 3 and EU Stage 3A emissions certified
Governor	Electronically controlled
Fan Drive Type	Hydraulic
Fuel System	Direct injection
Maximum Torque	Gross 2089 N•m 213 kg•m
Transmission and speeds
Travel Speed	34.8 mph
Torque Converter	3-elements, 1-stage, 2-phase
Transmission	Full-automatic, counter-shaft type
Speed Range	6 speeds forward and 2 reverse
Lockup Clutch	Wet, single-disk clutch
Forward	Torque converter drive in 1st gear, direct drive in 1st lockup and all higher gears
Reverse	Torque converter drive and direct drive in all gear
Shift Control	Electronic shift control with automatic clutch modulation in all gear
Weights
Front Axle - Empty	56.9 %
Rear Axle - Empty	20 %
Front Axle - Loaded	29.4 %
Rear Axle - Loaded	35.2 %
Center Axle - Empty	23.1 %
Center Axle - Loaded	35.4 %
Gross Weight	163,418 lb
Empty Weight	75,056 lb
Steering System
Steering System Type	Articulated type, fully hydraulic power steering with two double acting cylinders
Supplementary Steering	Automatically actuated electrically powered
Minimum Turning Radius, Wall To Wal	8.80 m
Articulation Angle	45°each direction
Electrical System
Alternator	24V, 75 Ah
Batteries	12V, 136 Ah x 2
Starter Motor	24V, 11.0 kW
Suspension System
Rear	Combined hydro-pneumatic and rubber suspension system
Front	Hydro-pneumatic suspension
Main Frame
Main Frame Type	Articulated type, box-sectioned construction on front and rear Connected by strong torque tubes
Body
Capacity Struck	23.9 yd3
Heaped (2:1, SAE)	31.4 yd3
Payload	40.0 metric tons
Material	130 kg/mm2 high tensile strength steel
Material Thickness-Bottom	0.6 in
Material Thickness-Front	0.4 in
Material Thickness-Sides	0.5 in
Target Area	5,667 mm x 3194 mm
Heating	Exhaust heating (option)
Capacities
Fuel Tank - Diesel	136.9 gal
Final Drive	8.5 gal
Engine Oil	13.3 gal
Torque Converter, Transmission And Retarder Cooling	33.1 gal
Differentials	28.6 gal
Suspension	5.4 gal
Tires
Standard Tire	29.5 R25
Axles
Differential	3.727
Planetary	4.941
Hydraulic System
Hoist Cylinder	Twin, telescopic type
Hoist Time	12 sec
Relief Pressure	28.4 MPa 290 kg/cm2 Hoist time
Cab
Compliance	Comply with ISO 3471 ROPS (Roll-Over Protective Structure) standard, and ISO 3449 FOPS (Falling Objects Protective Structure : Level II)Standard
Brakes
Service Brake	Full Hydraulic control, oil cooled , multiple disc type on front and centre axles
Parking Brake	Spring applied, caliper disc type
Retarder	Front and center axle brakes act as retarder
Additional specifications
Standard	ISO5010, SAE J1511
Hydraulic System	44.2 gal

Source

Compare Komatsu HM300-2, HM400-3M0

Dimensions and weight
Specification	HM300-2	HM400-3M0
Overall Length	34.26 ft	36.44 ft
Overall Width	9.52 ft	11.32 ft
Overall Height	11.55 ft	12.26 ft
Ground Clearance	1.68 ft	2.33 ft
Turning Radius – Outside Minimum	26.09 ft	28.88 ft
Tyre Gauge	7.49 ft	9.72 ft

Steering System
Specification	HM300-2	HM400-3M0
Steering System Type	Articulated type, fully hydraulic power steering with two double-acting cylinders	Articulated type, fully hydraulic power steering with two double acting cylinders
Supplementary Steering	Automatically actuated electrically powered	Automatically actuated electrically powered
Articulation Angle	45°each direction	45°each direction

Electrical System
Specification	HM300-2	HM400-3M0
Alternator	24V, 75 Ah	24V, 75 Ah
Batteries	12V, 136 Ah x 2	12V, 136 Ah x 2
Starter Motor	24V, 11.0 kW	24V, 11.0 kW

Suspension System
Specification	HM300-2	HM400-3M0
Rear	Combined hydro-pneumatic and rubber suspension system	Combined hydro-pneumatic and rubber suspension system
Front	Hydro-pneumatic suspension	Hydro-pneumatic suspension

Main Frame
Specification	HM300-2	HM400-3M0
Main Frame Type	Articulated type, box-sectioned construction on front and rear Connected by strong torque tubes	Articulated type, box-sectioned construction on front and rear Connected by strong torque tubes

Body
Specification	HM300-2	HM400-3M0
Capacity Struck	16.9 yd3	23.9 yd3
Heaped (2:1, SAE)	21.7 yd3	31.4 yd3
Payload	27.3 metric tons 30.1 US tons	40.0 metric tons
Material	130 kg/mm2 184,925 psi high tensile strength steel	130 kg/mm2 high tensile strength steel
Material Thickness-Bottom	0.6 in	0.6 in
Material Thickness-Front	0.4 in	0.4 in
Material Thickness-Sides	0.5 in	0.5 in
Heating	Exhaust heating (option)	Exhaust heating (option)

Engine
Specification	HM300-2	HM400-3M0
Number Of Cylinders	6	6
Engine Model	Komatsu SAA6D125E-5	Komatsu SAA6D140E-5
Engine Type	Water-cooled, 4-cycle	Water-cooled, 4-cycle
Gross Power	340 hp	453 hp
Lubrication	Method- Gear pump, force-lubrication Filter-Full-flow type	Method- Gear pump, force-lubrication Filter-Full-flow type
Air Cleaner	Dry type with double elements and precleaner (cyclonpack type), plus dust indicator EPA Tier 3 and EU Stage 3A emissions certified	Dry type with double elements and precleaner, plus dust indicator *Net horsepower at the maximum speed of radiator cooling fan is 307 kW 411 HP EPA Tier 3 and EU Stage 3A emissions certified
Governor	Electronically controlled	Electronically controlled
Net Power	329 hp	448 hp
Power Measured @	2,000 rpm	2,000 rpm
Aspiration	Turbo-charged, after-cooled, cooled EGR	Turbo-charged, after-cooled, cooled EGR
Displacement	674 cu in	930.1 cu in
Bore	5 in	5.6 in
Stroke	6 in	6.5 in
Fan Drive Type	Mechanical	Hydraulic
Fuel System	Direct injection	Direct injection
Maximum Torque	174 kg•m 1,259 lb ft	Gross 2089 N•m 213 kg•m

Capacities
Specification	HM300-2	HM400-3M0
Fuel Tank - Diesel	101.5 gal	136.9 gal
Final Drive	6.3 gal	8.5 gal
Hydraulic System	31.7 gal	44.2 gal
Engine Oil	9.8 gal	13.3 gal
Torque Converter, Transmission And Retarder Cooling	20.5 gal	33.1 gal
Differentials	16.8 gal	28.6 gal
Suspension	2.7 gal	5.4 gal

Transmission and speeds
Specification	HM300-2	HM400-3M0
Travel Speed	36.4 mph	34.8 mph
Torque Converter	3-elements, 1-stage, 2-phase	3-elements, 1-stage, 2-phase
Transmission	Full-automatic, counter-shaft type	Full-automatic, counter-shaft type
Speed Range	6 speeds forward and 2 reverse	6 speeds forward and 2 reverse
Lockup Clutch	Wet, single-disk clutch	Wet, single-disk clutch
Forward	Torque converter drive in 1st gear, direct drive in 1st lockup and all higher gears	Torque converter drive in 1st gear, direct drive in 1st lockup and all higher gears
Reverse	Torque converter drive and direct drive in all gear	Torque converter drive and direct drive in all gear
Shift Control	Electronic shift control with automatic clutch modulation in all gear	Electronic shift control with automatic clutch modulation in all gear

Weights
Specification	HM300-2	HM400-3M0
Gross Weight	113,360 lb	163,418 lb
Empty Weight	53,000 lb	75,056 lb
Front Axle - Empty	55.8 %	56.9 %
Center Axle - Empty	23.6 %	23.1 %
Rear Axle - Empty	20.6 %	20 %
Front Axle - Loaded	30.3 %	29.4 %
Center Axle - Loaded	35.5 %	35.4 %
Rear Axle - Loaded	34.2 %	35.2 %

Tires
Specification	HM300-2	HM400-3M0
Standard Tire	23.5 R25	29.5 R25

Axles
Specification	HM300-2	HM400-3M0
Differential	3.154	3.727
Planetary	4.667	4.941

Hydraulic System
Specification	HM300-2	HM400-3M0
Hoist Cylinder	Twin, 2-stage telescopic type	Twin, telescopic type
Relief Pressure	20.6 MPa 210 kg/cm2 2,990 psi	28.4 MPa 290 kg/cm2 Hoist time
Hoist Time	12 sec	12 sec

Cab
Specification	HM300-2	HM400-3M0
Compliance	Dimensions comply with ISO 3471 ROPS (Roll-Over Protective Structure) standard	Comply with ISO 3471 ROPS (Roll-Over Protective Structure) standard, and ISO 3449 FOPS (Falling Objects Protective Structure : Level II)Standard

Brakes
Specification	HM300-2	HM400-3M0
Service Brake	Full-hydraulic control, oil-cooled multiple-disc type on front and center axles	Full Hydraulic control, oil cooled , multiple disc type on front and centre axles
Parking Brake	Spring applied, caliper disc type	Spring applied, caliper disc type
Retarder	Front and center axle brakes act as retarder	Front and center axle brakes act as retarder

More in Komatsu: HM350-2, HM300-5, HM300-3/HM400-3.

Komatsu HM300-2 and HM400-3M0 specifications

HM300-2 and HM400-3M0: owner reports

History and service record of HM300-2 and HM400-3M0

Sources for this page

Komatsu HM300-2 and HM400-3M0: Configuration records