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Large dozer

D155AX-8

  • Horsepower 264 kW @ 1 900 rpm 354 HP @ 1,900 rpm
  • Operating weight 40 506 kg 89,300 lbs.
  • Blade capacity 9.4 - 11.9 m³ 12.3 - 15.6 yd³

Torque converter dozers for your heavy jobs

Your big jobs demand a big dozer. 350+ horsepower, massive blade capacity with semi-U and full U blades, automatic lockup torque converter, and low drive K-bogie suspended undercarriage designed for maximum traction and smooth ride when dozing or ripping.

  • Engineered for powerful dozing
  • Excellent blade capacity
  • Quiet cab with smooth ride and great visibility
  • Automated blade control with iMC

Features and benefits

Custom build the dozer you need

All the dozers in the D65/85/155 family offer you outstanding power, economy and reliability. Customize yours with the blade (straight, Semi-U, Sigmadozer and Full U (D155 only)), track shoe width and horsepower combo best suited to your particular application.

Helps minimize fuel use

An advanced Tier 4 engine offers you a potent combo of power and fuel efficiency. An auto idle shutdown, adjustable from 5-60 minutes, also helps cut fuel use and emissions.

Controls help fight operator fatigue

Operators will enjoy the palm command electronic control joysticks that fit the natural relaxed shape of their hands. Auto-shift or manual-shift modes are easily selected with one push of a button for precision with less fatigue over the course of a shift.

Smooth, powerful handling

Your operators can execute smooth powerful turns with the hydrostatic steering system. It transmits engine power to both tracks without power interruption and minimizes turning radius with counter-rotation while in neutral.

Long-lasting undercarriage

Get the most from your dozer. The Parallel Link Undercarriage System (PLUS) with rotating bushings delivers up to twice the life of our conventional undercarriage with no pin and bushing turn required. Parts wear evenly and last longer before needing replacement.

Work with fuel-efficient power

Seek maximum work efficiency with a lock-up torque converter. It determines the appropriate gear based on load and conditions. The lockup mechanism then automatically transfers engine power directly to the transmission, helping boost drive train efficiency.

intelligent Machine Control (iMC)

With automatic dozing, rough cut to finish grade, iMC-equipped machines make every pass count. Dozers “learn” operator blade input. In select situations, operators can opt for near-100% auto control. And, iMC helps new operators get up to speed quickly.

Help operators stay focused

Your operators perform best when they’re comfortable. That’s why they’ll love the air suspension seat with lumbar support and tilt. It’s easy for them to adjust to suit their needs, and electric heat helps them stay comfortable in the cold.

Situational awareness

A standard rear camera monitoring system displays the view behind the dozer on the large color monitor in the cab.

No-hassle DPF regeneration

Tier 4 machines use diesel particulate filters to burn off engine soot via regeneration. To help make sure it rarely impacts your operation, all D65/D85/D155 models use continuous passive regeneration, and active regeneration that typically doesn’t require the dozer to stop.

Efficient blade pitch operation

Pressing the auto-pitch switch* lets the operator toggle blade pitch position from dig to dump with no lever movements. The blade pitch control can be set to automatically return to the digging position when reverse is selected. * Requires dual tilt dozer

Ergonomic ripper controls

Operators will love the ergonomic ripper control lever that incorporates an auto-return function. It automatically raises the ripper so they can stop grappling with levers and focus on other tasks. It kicks in when travel lever is moved to reverse.

Specifications for D155AX-8

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US system Metric
Engine
Model Komatsu SAA6D140E-7**
Type 4-cycle, water-cooled, direct injection
Aspiration Komatsu Variable Geometry Turbocharged, air-to-air aftercooled, cooled EGR
Number of cylinders 6
Bore x stroke 140 x 165 mm
Piston displacement 15.24 L
Governor Mid-range, electronic
Horsepower:
SAE J1995 - Gross 268 kW
ISO 9249 / SAE J1349* - Net 264 kW
Rated rpm 1 900 rpm
Fan drive type Hydraulic
Lubrication system:
Method Gear pump, force lubrication
Filter Full-flow
*Net horsepower at the maximum speed of radiator cooling fan: 239 kW 
**EPA Tier 4 Final emissions certified
Model Komatsu SAA6D140E-7**
Type 4-cycle, water-cooled, direct injection
Aspiration Komatsu Variable Geometry Turbocharged, air-to-air aftercooled, cooled EGR
Number of cylinders 6
Bore x stroke 5.51 x 6.50 in
Piston displacement 930 in³
Governor Mid-range, electronic
Horsepower:
SAE J1995 - Gross 360 HP
ISO 9249 / SAE J1349* - Net 354 HP
Rated rpm 1,900 rpm
Fan drive type Hydraulic
Lubrication system:
Method Gear pump, force lubrication
Filter Full-flow
*Net horsepower at the maximum speed of radiator cooling fan: 320 HP
**EPA Tier 4 Final emissions certified
Final Drive
Double-reduction, spur and planetary final drives increase tractive effort. Segmented sprockets are bolt-on for easy in-the-field replacement.
Double-reduction, spur and planetary final drives increase tractive effort. Segmented sprockets are bolt-on for easy in-the-field replacement.
Hydraulic System

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 325 L/min for steering and 180 L/min for implement at rated engine rpm.

Relief valve setting
. . . for implement 27.5 MPa 280 kg/cm² 
. . . for steering 38.2 MPa 390 kg/cm² 

Control valves:
Spool control valve for SIGMADOZER, Semi-U tilt dozer and Full-U tilt dozer.
Positions: 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.
Positions: Ripper lift Raise, hold, and lower
Ripper tilt Increase, hold, and decrease
Hydraulic cylinders Double-acting, piston
Number of cylinders Bore
Blade Lift / 2 110 mm
Blade Tilt (Dual tilt) / 2 160 mm
Blade Tilt (Single Tilt) / 1 160 mm
Ripper Lift 180 mm
Ripper Tilt / 1 200 mm
Hydraulic oil capacity (refill):
SIGMADOZER 95 L
Semi-U dozer 95 L
Full-U dozer 95 L
Ripper equipment (additional volume):
Multi-shank ripper 37 L
Giant ripper 37 L

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 85.9 US gal for steering and 47.6 US gal for implement at rated engine rpm.

Relief valve setting
. . . for implement 3,980 psi
. . . for steering 5,550 psi

Control valves:
Spool control valve for SIGMADOZER, Semi-U tilt dozer and Full-U tilt dozer.
Positions: 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.
Positions: Ripper lift Raise, hold, and lower
Ripper tilt Increase, hold, and decrease
Hydraulic cylinders Double-acting, piston
Number of cylinders Bore
Blade Lift / 2 4.33 in
Blade Tilt (Dual tilt) / 2 6.30 in
Blade Tilt (Single Tilt) / 1 6.30 in
Ripper Lift 7.09 in
Ripper Tilt / 1 7.87 in
Hydraulic oil capacity (refill):
SIGMADOZER 25.1 US gal
Semi-U dozer 25.1 US gal
Full-U dozer 25.1 US gal
Ripper equipment (additional volume):
Multi-shank ripper 9.8 US gal
Giant ripper 9.8 US gal
Operating Weight
Tractor weight
Including rated capacity of lubricant, coolant, full fuel tank, operator, and standard equipment (including ROPS cab).
632 700 kg
Operating weight
Including strengthened SIGMADOZER, giant ripper, ROPS cab, operator, standard equipment, rated capacity of lubricant, coolant, and full fuel tank.
40 500 kg
Ground pressure 99.5 kPa / 1.01 kg/cm²
Tractor weight
Including rated capacity of lubricant, coolant, full fuel tank, operator, and standard equipment (including ROPS cab).
72,100 lbs.
Operating weight
Including strengthened SIGMADOZER, giant ripper, ROPS cab, operator, standard equipment, rated capacity of lubricant, coolant, and full fuel tank.
89,300 lbs.
Ground pressure 14.4 psi
Service Refill Capacities
Fuel tank 625 L
Coolant 104 L
Engine oil 37 L
Damper 1.5 L
Transmission, bevel gear, and steering system 90 L
Final drive (each side) 31 L
DEF tank 39 L
Hydraulic oil capacity 95 L
Fuel tank 165 US gal
Coolant 27.5 US gal
Engine oil 9.8 US gal
Damper 0.4 US gal
Transmission, bevel gear, and steering system 23.8 US gal
Final drive (each side) 8.2 US gal
DEF tank 10.3 US gal
Hydraulic oil capacity 25.1 US gal
Steering System

PCCS lever controls for all directional movements. Pushing the PCCS lever forward results in forward machine travel, while pulling it rearward reverses the machine. Simply tilt the PCCS lever to the left to make a left turn. Tilt it to the right for a right turn.

Hydrostatic steering system (HSS) is powered by steering planetary units and an independent hydraulic pump and motor. Counter-rotation turns are also available. Wet, multiple-disc, pedal-controlled service brakes are spring-actuated and hydraulically released. Gearshift lock lever also applies parking brakes.

Minimum turning radius 2.14 m

Palm Command Control System (PCCS) lever controls for all directional movements. Pushing the PCCS lever forward results in forward machine travel, while pulling it rearward reverses the machine. Simply tilt the PCCS lever to left to make a left turn. Tilt it to the right for a right turn.

Hydrostatic Steering System (HSS) is powered by steering planetary units and an independent hydraulic pump and motor. Counterrotation turns are also available. Wet, multiple-disc, pedal-controlled service brakes are spring-actuated and hydraulically released. Gear shift lock lever also applies parking brake.

Minimum turning radius 6 ft. 6 in
TORQFLOW Transmission

Komatsu's automatic TORQFLOW transmission consists of a water-cooled, 3-element, 1-stage, 1-phase, torque converter with lockup clutch, and a planetary gear, multipledisc clutch transmission which is hydraulically actuated and force-lubricated for optimum heat dissipation. Equipped with gearshift lock lever and neutral safety switch.

Travel speed:
1st Gear forward 3.8 kph
1st Gear reverse 4.6 kph
2nd Gear forward 5.6 kph
2nd Gear reverse 6.8 kph
3rd L Gear forward 7.5 kph
3rd L Gear reverse 9.2 kph
3rd Gear forward 11.6 kph
3rd Gear reverse 14.0 kph

Komatsu's automatic TORQFLOW transmission consists of a water-cooled, 3-element, 1-stage, 1-phase, torque converter with lockup clutch, and a planetary gear, multipledisc clutch transmission which is hydraulically actuated and force-lubricated for optimum heat dissipation. Equipped with gearshift lock lever and neutral safety switch.

Travel speed:
1st Gear forward 2.4 mph
1st Gear reverse  2.9 mph
2nd Gear forward  3.5 mph
2nd Gear reverse  4.2 mph
3rd L Gear forward  4.7 mph
3rd L Gear reverse  5.7 mph
3rd Gear forward  7.2 mph
3rd Gear reverse  8.7 mph
Undercarriage

Suspension: Oscillation-type with equalizer bar and forward mounted pivot shafts

Track roller frame: Monocoque, high-tensilestrength steel construction

K-Bogie undercarriage
Lubricated track rollers are resiliently mounted the track frame with a bogie suspension system whose oscillating motion is cushioned by rubber pads.

Track shoes
Lubricated tracks. Unique dust seals for preventing entry of foreign abrasives into pin-to-bushing clearance for extended service. Track tension easily adjusted with grease gun.

Number of shoes (each side) 42
Grouser height 80 mm
Shoe width (standard/maximum) 610 mm / 710 mm
Ground contact area 39 955 cm²
Ground pressure (tractor only) 80.3 kPa / 0.82 kg/cm²
Number of track rollers (each side) 7
Number of carrier rollers (each side) 2

Suspension: Oscillation-type with equalizer bar and forward mounted pivot shafts

Track roller frame: Monocoque, high-tensilestrength steel construction

K-Bogie undercarriage
Lubricated track rollers are resiliently mounted the track frame with a bogie suspension system whose oscillating motion is cushioned by rubber pads.

Track shoes
Lubricated tracks. Unique dust seals for preventing entry of foreign abrasives into pin-to-bushing clearance for extended service. Track tension easily adjusted with grease gun.

Number of shoes (each side) 42
Grouser height 3.1 in
Shoe width (standard/maximum) 24 in / 28 in
Ground contact area 6,193 in²
Ground pressure (tractor only) 11.6 psi
Number of track rollers (each side) 7
Number of carrier rollers (each side) 2
  • Air cleaner, double element with dust indicator
  • Alternator, 140 ampere/24V
  • Backup alarm
  • Batteries, 200 Ah/2 x 12V
  • Battery disconnect switch
  • Blade lift cylinders with double dust seal
  • Color monitor, LCD
  • Decelerator pedal
  • Engine hood
  • Engine idle auto shutdown with adjustable timer
  • Engine intake centrifugal precleaner
  • Engine, gull-wing side covers
  • Engine shutdown secondary switch
  • Exhaust pipe with raincap
  • Fast fuel provision
  • Fenders
  • Front pull hook
  • Fuel pre-filter and primary filter
  • Grid heater starting aid in cold weather
  • High mount foot rests
  • Horn, warning
  • Hydraulic driven radiator cooling fan with manual reverse clean mode
  • Hydraulics for dual tilt and pitch dozer
  • Hydraulics for ripper VGR/MSR
  • KOMTRAX® Level 5
  • K-bogie undercarriage
  • Komatsu Diesel Particulate Filter (KDPF)
  • Komatsu Variable Geometry Turbocharger (KVGT)
  • Komatsu Selective Catalytic Reduction (SCR)
  • Locks, filler caps and covers
  • Oil pressure check ports for power train
  • PM service connector
  • Radiator mask, double door, heavy-duty, hinged, perforated
  • Radiator reserve tank
  • Rear cover
  • ROPS cab (1420 kg)**
  • Air conditioner/heater/defroster
    --Pressurized
    --Condenser remote mounted
  • Cab accessories
  • Work lights
    --2 front, hood mounted
    --2 front, cab mounted
    --2 rear, fender mounter
    --2 rear, cab mounted
    --1 rear, for ripper point
  • Seat, air suspension, fabric, heated, low back, rotates 12.5° to right, headrest
  • Seat belt, 76 mm, retractable
  • Seat belt indicator
  • Sealed electrical connectors
  • Starting motor, 11.0 kW
  • Steering system: Hydrostatic Steering System (HSS)
  • Torque converter with auto lock-up
  • Track roller guards, end sections
  • Track shoe assembly
  • Sealed and lubricated
  • 610 mmextreme service shoes
  • Transmission with auto/manual shift modes
  • Underguards, heavy duty
  • Hinged belly pans
  • Water separator, fuel
  • Wide core cooling package, 6 fins per inch spacing
  • Air cleaner, double element with dust indicator
  • Alternator, 140 ampere/24V
  • Backup alarm
  • Batteries, 200 Ah/2 x 12V
  • Battery disconnect switch
  • Blade lift cylinders with double dust seal
  • Color monitor, LCD
  • Decelerator pedal
  • Engine hood
  • Engine idle auto shutdown with adjustable timer
  • Engine intake centrifugal precleaner
  • Engine, gull-wing side covers
  • Engine shutdown secondary switch
  • Exhaust pipe with raincap
  • Fast fuel provision
  • Fenders
  • Front pull hook
  • Fuel pre-filter and primary filter
  • Grid heater starting aid in cold weather
  • High mount foot rests
  • Horn, warning
  • Hydraulic driven radiator cooling fan with manual reverse clean mode
  • Hydraulics for dual tilt and pitch dozer
  • Hydraulics for ripper VGR/MSR
  • KOMTRAX® Level 5
  • K-bogie undercarriage
  • Komatsu Diesel Particulate Filter (KDPF)
  • Komatsu Variable Geometry Turbocharger (KVGT)
  • Komatsu Selective Catalytic Reduction (SCR)
  • Locks, filler caps and covers
  • Oil pressure check ports for power train
  • PM service connector
  • Radiator mask, double door, heavy-duty, hinged, perforated
  • Radiator reserve tank
  • Rear cover
  • ROPS cab (3,131 lb)**
  • Air conditioner/heater/defroster
    --Pressurized
    --Condenser remote mounted
  • Cab accessories
  • Work lights
    --2 front, hood mounted
    --2 front, cab mounted
    --2 rear, fender mounter
    --2 rear, cab mounted
    --1 rear, for ripper point
  • Seat, air suspension, fabric, heated, low back, rotates 12.5° to right, headrest
  • Seat belt, 3", retractable
  • Seat belt indicator
  • Sealed electrical connectors
  • Starting motor, 24V
  • Steering system: Hydrostatic Steering System (HSS)
  • Torque converter with auto lock-up
  • Track roller guards, end sections
  • Track shoe assembly
  • Sealed and lubricated
  • 24" extreme service shoes
  • Transmission with auto/manual shift modes
  • Underguards, heavy duty
  • Hinged belly pans
  • Water separator, fuel
  • Wide core cooling package, 6 fins per inch spacing

Shoes, single grouser - Additional weight:

  • 26" extreme service: +240 kg
  • 28" moderate service: No additional
  • 24" PLUS extreme service: +569 kg
  • 26" PLUS extreme service: +819 kg
  • 28" PLUS extreme service: +1029 kg

Shoes, single grouser - Ground contact area:

  • 26" extreme service: 43 230 cm2
  • 28" moderate service: 46 505 cm2
  • 24" PLUS extreme service: 39 955 cm2
  • 26" PLUS extreme service: 43 230 cm2
  • 28" PLUS extreme service: 46 505 cm22

Variable Multi-Shank Ripper:

  • Additional weight (including hydraulic control unit): 3760 kg 
  • Beam length: 2320 mm 
  • Hydraulically-controlled parallelogram-type ripper with three shanks. Digging angle infinitely adjustable. Standard digging angle: 49°
  • Maximum digging depth: 900 mm
  • Maximum lift above ground: 950 mm 

Variable Giant Ripper:

  • Additional weight (including hydraulic control unit): 2440 kg 
  • Beam length: 1400 mm 
  • Hydraulically-controlled parallelogram-type ripper with one shank. Digging angle infinitely adjustable. Standard digging angle: 49°
  • Maximum digging depth: 1240 mm 
  • Maximum lift above ground: 950 mm 

Other:

  • HD Counterweight 9-plate with rigid drawbar, 3568 kg
  • Sigma push group (bladeless) for Allied blade

Dozer Equipment:

  • SIGMADOZER®
  • Full-U
  • Semi-U

Shoes, single grouser - Additional weight:

  • 26" extreme service: +530 lb
  • 28" moderate service: No additional
  • 24" PLUS extreme service: +1,254 lb
  • 26" PLUS extreme service: +1,806 lb
  • 28" PLUS extreme service: +2,269 lb

Shoes, single grouser - Ground contact area:

  • 26" extreme service: 6,700 in2
  • 28" moderate service: 7,208 in2
  • 24" PLUS extreme service: 6,193 in2
  • 26" PLUS extreme service: 6,700 in2
  • 28" PLUS extreme service: 7,208 in2

Variable Multi-Shank Ripper:

  • Additional weight (including hydraulic control unit): 8,290 lb
  • Beam length: 7'7"
  • Hydraulically-controlled parallelogram-type ripper with three shanks. Digging angle infinitely adjustable. Standard digging angle: 49°
  • Maximum digging depth: 2'11"
  • Maximum lift above ground: 3'1"

Variable Giant Ripper:

  • Additional weight (including hydraulic control unit): 5,380 lb
  • Beam length: 4'7"
  • Hydraulically-controlled parallelogram-type ripper with one shank. Digging angle infinitely adjustable. Standard digging angle: 49°
  • Maximum digging depth: 4'1"
  • Maximum lift above ground: 3'1"

Other:

  • HD Counterweight 9-plate with rigid drawbar, 7,860 lb
  • Sigma push group (bladeless) for Allied blade

Dozer Equipment:

  • SIGMADOZER®
  • Full-U
  • Semi-U
Support you can count on

Technology that works as hard as you do

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Komtrax for construction equipment is Komatsu’s state of the art remote monitoring system, helping you keep track of where your machines are and how much they are working. The system seamlessly gathers important data that can help you coach operators to improve efficiencies and productivity.

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