New Tier 4 Final Engine

The Komatsu SAA6D140E-7 engine is EPA Tier 4 Final emissions certified and provides exceptional performance while reducing fuel consumption. Based on Komatsu proprietary technologies developed over many years, this new diesel engine reduces nitrogen oxides (NOx) by more than 80% when compared to Tier 4 interim levels. Through the in-house development and production of engines, electronics, and hydraulic components, Komatsu has achieved great advancements in technology, providing high levels of performance and efficiency in virtually all applications.

Heavy-duty aftertreatment system

This new system combines a Komatsu Diesel Particulate Filter (KDPF) and Selective Catalytic Reduction (SCR). The SCR NOx reduction system injects the correct amount of DEF at the proper rate, thereby decomposing NOx into non-toxic water (H₂O) and nitrogen gas (N₂).

New Fuel Efficient Bulldozer

New D155AX-8 has achieved both high levels of productivity and fuel economy through usage of SIGMADOZER and automatic transmission with lockup torque converter.

Auto-pitch Mode*

To reduce operator effort and increase operating efficiency the new auto blade pitch mode sets blade pitch position between digging and dump positions while dozing. By pressing the autopitch switch it will toggle the pitch position from digging to dump position with no additional lever movements. The blade pitch control can be set through the monitor to automatically return to the digging position when reverse is selected.

* Requires dual tilt dozer

Ripper Auto-return

The ripper control lever is new, ergonomic and incorporates an auto-return function that will automatically raise the ripper so the operator is less fatigued at the end of the day. The function starts when travel lever is moved to reverse position.

Komatsu Auto Idle Shutdown

Komatsu auto idle shutdown automatically shuts the engine down after idling for a set period of time to reduce unnecessary fuel consumption and exhaust emissions. The amount of time before the engine is shutdown can be easily programmed from 5 to 60 minutes.

Engine

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.

Final Drive

Double-reduction, spur and planetary final drives increase tractive effort. Segmented sprockets are bolt-on for easy in-the-field replacement.

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.

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.

Service Refill Capacities

Operating Weight

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/min85.9 U.S. gal for steering and 180 L/min 47.6 U.S. gal for implement at rated engine rpm.

Relief valve setting
. . . for implement 27.5 MPa 280 kg/cm² 3,980 psi
. . . for steering 38.2 MPa 390 kg/cm² 5,550 psi