• 157,940 lbs Operating Weight
  • 610 @1800 rpm Horsepower
  • 24.2 yd³ Blade Capacity


The D375A-6 is a great combination of power and balance; power for digging and pushing, balance for stability on slopes and for ripping. Giant or multi-shank rippers are available as is a wide lighting and maintenance options specifically designed for the demands of the mining industry. A lock-up torque converter lets the D375A-6 to shift into direct drive when pushing to increase speed and production.


Automatic Torque Converter Lockup System

For greater efficiency during long pushes, the lockup mode allows the system to automatically engage the torque converter lockup clutch. Locking up the torque converter transmits all the engine power directly to the transmission, increasing ground speed and thus achieving efficiencies equal to a direct drive. The results of this efficient use of engine power are less fuel consumption and faster cycle times.

Effect of ECMV Steering Clutches/Brake Control

When dozing downhill, ECMV automatically controls steering clutches and brakes depending on incline of machine or degree of load, reducing counter-steering and producing smooth dozing operation.

When dozing and turning, ECMV automatically controls stroke ratio of steering clutches and brakes depending on degree of load, enabling smooth dozing and turning.

Electronic Controlled Modulation Valve (ECMV) 


The controller automatically adjusts each clutch engagement depending on travel conditions such as gear speed, RPM and shifting pattern. This provides shockless and smooth clutch engagement, improved component reliability, extended component life, and operator ride comfort.

Steering Clutches/Brakes

Sensors monitor machine operating conditions and electronically control the steering clutches and brakes. Monitoring application parameters such as incline angle of slope and degree of load provides smooth and easy operation by reducing counter-steering on downhill travel, etc.

Fully Adjustable Air Suspension Seat and Travel Control Console

For improved rear visibility during the return portion of the cycle, the operator can adjust the seat 15° to the right. The transmission and steering controls move with the seat for optimum operator comfort. The travel control console is adjustable fore, aft, and for height. The armrest is independently adjustable up and down, providing optimum operation posture for all operators. The operator seat is also tiltable for facilitating downhill dozing.

K-Bogie Undercarriage System

K-Bogies with front and rear single bogies are utilized to increase the length of track on ground improving machine stability and leveling performance. An oscillating idler and increased sprocket lead angle improve riding comfort when traveling over rough terrain. K-Bogies oscillate with two fulcrums assuring a large amount of track roller vertical travel. Impact load to undercarriage components is minimized and durability of components is improved since track rollers are always in contact with track links. Track rollers follow track link movement to extend the undercarriage life. Excellent riding comfort is provided due to less vibration and shock when traveling over rough terrain.

Palm Command Electronic Controlled Travel Control Joystick

Ergonomically designed palm command travel joystick provides the operator with a relaxed posture and superb control improving operator comfort. Transmission gear shifting is simply carried out with thumb push buttons.

Palm Command PPC Controlled Blade Control Joystick

The blade control joystick uses the Proportional Pressure Control (PPC) valve and joystick, similar to the travel control joystick. PPC control combined with the highly reliable Komatsu hydraulic system enables superb control. Dual tilt and pitch operation are enabled by pressing a switch with the thumb.

Track Link With Wedge Ring

New D375A-6 track links feature reduced press-fit force and a wedge ring. Conventional track pins are retained only with a large press-fit force. (The new track link divides pin forces between the wedge ring and press-fit force.) This enables easier service with reduced pin damage when turning pins and bushings. The result is improved undercarriage life and reduced maintenance cost through reduced wear, greater pin reusability, and reduced maintenance man-hours.

Track Shoe Slip Control Mode

Eliminates the need for the operator to constantly control engine power output with the decelerator pedal while ripping substantially reducing operator fatigue. Maneuverability is improved because the operator is free to focus on the ripping application without having to monitor the track shoe slippage. Repair costs are significantly lowered and undercarriage life is extended with the reduction in track shoe slippage. The track shoe slip control system will contribute to lower fuel costs because the engine output is automatically controlled to optimum levels for operation.

Working Mode

This mode can be set to either “P mode” for maximum production (power) or “E mode” for energy saving operation (economy). Combined with the automatic gearshift mode or manual gearshift mode, the working mode allows the operator to select the optimum machine operating condition for the work at hand. (The mode can be switched during operation.)


Coolant and Lubricant Capacity (refill)

Fuel tank317.0 U.S. gal1200 ltr
Coolant31.7 U.S. gal120 ltr
Engine22.7 U.S. gal86 ltr
Torque converter, transmission, bevel gear, and steering system39.6 U.S. gal150 ltr
Final drive (each side)17.1 U.S. gal65 ltr


Model Komatsu SAA6D170E-5*
Type 4-cycle, water-cooled, direct injection
Aspiration Turbocharged, air-to-air aftercooled, cooled EGR
Number of cylinders 6
Bore x stroke 6.69" x 6.69" 170 mm x 170 mm
Piston displacement 1,413 in³ 23.15 ltr
Governor All-speed and mid-range, electronic
SAE J1995 - Gross 636 HP 474 kW
ISO 9249 / SAE J1349 - Net 610 HP 455 kW
Hydraulic fan at maximum speed - Net 580 HP 433 kW
Rated rpm 1800 rpm
Fan drive type Hydraulic
Lubrication system:
Method Gear pump, force lubrication
Filter Full-flow

Final Drive

Double-reduction final drive of spur and planetary gear sets to increase tractive effort and reduce gear tooth stresses for long final drive life. Segmented sprocket teeth are bolt-on for easy replacement.

Hydraulic System

Hydraulic control unit:
Closed-center load sensing system (CLSS) designed for precise and responsive control, and for efficient simultaneous operation.
Hydraulic control unit:
All spool control valves externally mounted beside the hydraulic tank. Variable piston pump with capacity (discharge flow) of 366 ltr/min / 96.7 U.S. gal/min for implement at rated engine rpm.
Relief valve setting . . . for implement 3,980 psi 27.5 MPa
280 kg/cm²
Control valves:
Spool control valves for Semi-U tilt dozer and Full-U tilt dozer.
Blade lift Raise, hold, lower, and float
Blade tilt Right, hold, and left
Additional control valve required for variable digging angle multi-shank ripper and giant ripper.
Ripper lift Raise, hold, and lower
Ripper tilt Increase, hold, and decrease
Hydraulic cylinders:
Double-acting, piston
Number of cylinders: Bore:
Blade lift 2 5.5" / 140 mm
Blade tilt 1 7.1" / 180 mm
Ripper lift 2 7.9" / 200 mm
Ripper tilt 2 7.1" / 180 mm
Hydraulic oil capacity (refill):
Semi-U dozer or U dozer 34.4 U.S. gal 130 ltr
Ripper equipment (additional volume):
Giant ripper (variable) 11.9 U.S. gal 45 ltr
Multi-shank ripper (variable) 11.9 U.S. gal 45 ltr

Operating Weight

Tractor weight 117,290 lb 53200 kg
 Including rated capacity of lubricant, coolant, full fuel tank, operator, and standard equipment.
Including Semi-U tilt dozer, giant ripper, cab, ROPS, operator, standard equipment, rated capacity of lubricant, coolant, and full fuel tank. 157,940 lb 71640 kg
Ground pressure 21.0 psi 1.48 kg/cm² / 145 kPa

Steering System

PCCS, joystick controlled, wet multiple-disc steering clutches are spring-loaded and hydraulically released.Wet multiple-disc, pedal/lever controlled steering brakes are spring-actuated hydraulically released and require no adjustment. Steering clutches and brakes are interconnected for easy, responsive steering.

Minimum turning radius13'9"4.2 m

TORQFLOW Transmission

Komatsu TORQFLOW transmission consists of a water-cooled, 3-element, 1-stage, 1-phase torque converter with lockup clutch and a planetary gear, multiple-disc clutch transmission which is hydraulically actuated and force-lubricated for optimum heat dissipation. Gearshift lock lever and neutral safety switch help prevent accidental starts.

1st2.2 mph
3.5 km/h
2.9 mph
4.6 km/h
2nd4.2 mph
6.8 km/h
5.5 mph
8.9 km/h
3rd L5.0 mph
8.0 km/h
6.0 mph
9.7 km/h
3rd7.3 mph
11.8 km/h
9.8 mph
15.8 km/h


Suspension Oscillating equalizer bar and pivot shaft
Track roller frame Cylindrical, high-tensile-strength steel construction
Rollers and idlers Lubricated track rollers
K-Bogie undercarriage Lubricated track rollers are resiliently mounted to the track frame with a bogie suspension system whose oscillating motion is cushioned by rubber pads.
Extreme service track shoes Lubricated tracks. Unique seals prevent entry of foreign abrasives into pin to bushing clearances to provide extended service life. Track tension is easily adjusted with grease gun.
Number of shoes (each side) 41
Grouser height:
Single grouser 3.7" 93 mm
Shoe width (standard) 24" 610 mm
Ground contact area 7,527 in² 48560 cm²
Ground pressure (tractor) 15.6 psi 108 kPa / 1.10 kg/cm²
Number of track rollers 8
Number of carrier rollers 2
Extreme service shoes: Ground contact area: Ground** pressure:
24'' / 610 mm
Additional weight - 0 lb / 0 kg
7,527 in²
48560 cm²
21.0 psi
1.48 kgf/cm² / 145 kPa
28'' / 710 mm
Additional weight - 1,500 lb / 680 kg
8,760 in²
56520 cm²
18.2 psi
1.28 kgf/cm² / 126 kPa
32'' / 810 mm
Additional weight - 3,000 lb / 1360 kg
9,990 in²
64480 cm²
16.0 psi
1.13 kgf/cm² / 111 kPa
** Ground pressure based on tractor, Semi-U tilt dozer, giant ripper, cab, ROPS, operator, standard equipment, rated capacity of lubricant, coolant, and full fuel tank.


  • Accessory sockets, 2x12V
  • Air conditioner with heater and defroster
  • Alternator, 90 ampere/24V
  • Back-up alarm
  • Batteries, 2X12V, 200 Ah
  • Blower cooling fan
  • Car stereo
  • Decelerator pedal
  • Dry-type air cleaner with dust evacuator and dust indicator
  • Dual tilt dozer
  • Eight-roller track frames
  • Engine oil level sensor
  • Engine prelube
  • Final drive case wear guard
  • Hinged front mask
  • Hinged underguard with front pull hook
  • Hydraulics for ripper
  • Hydraulic track adjusters
  • K-Bogie Undercarriage System
  • KOMTRAX Plus
  • Lockup torque converter
  • Lunch box holder
  • Mirror, rear view
  • Monitor, large multi-color TFT LCD with self-diagnostic function
  • Muffler with rain cap
  • PCCS palm lever steering control
  • Perforated side covers
  • Radiator reserve tank
  • ROPS
  • Seat belt, 78 mm, 3"
  • Seat, air suspension, fabric, high back, fully adjustable
  • Shoes, 610 mm / 24" extreme service, single-grouser
  • Segmented sprockets
  • Spill guard for Full-U dozer
  • Starting motors, 2 x 7.5 kW/24V
  • Steps, heavy-duty and handles
  • Sun visor
  • TORQFLOW transmission
  • Track roller guards
  • Track shoe slip control system
  • Vandalism protection kit
  • Warning horn
  • Wet steering clutches


  • Additional front and rear work lights
  • Batteries and starter isolater box
  • Cab light uninterrupted power source
  • Canister-type breathers
  • Centralized grease points, ripper mount pin
  • Centralized grease points, blade cylinder yoke
  • Concentrated sampling points for oil and coolant
  • Fast fuel fill
  • High mounted headlights
  • Maintenance service center for oil and coolant
  • Manual engine stop switches
  • Provision for platforms
  • Rear view camera
  • Work light for the engine compartment