O
PERATOR
C
OMFORT
D39-22
CRAWLER DOZER
D39-22
C
R A W L E R
D
O Z E R
D
URABILITY
F
EATURES
HST with electronic control
The D39 is equipped with Komatsu-designed Hydrostatic
Transmission (HST) that allows for Quick-Shift or variable
speed selection. The HST consists of dual-path closed-
circuits with two variable displacement piston pumps and
two variable displacement travel motors. Hydrostatic
steering eliminates steering clutches and brakes, providing
smooth powerful turns. Fully electronic control provides full
automatic shifting and enables smooth control. Engine
speed is controlled using an electronic fuel control dial.
Comfortable ride with cab damper mounting
The D39’s cab mount uses a cab damper system that
provides excellent shock and vibration absorption which
conventional mounting systems are unable to match. The
silicon oil filled cab damper mount helps to isolate the cab
from the machine body, suppressing vibration and providing
a quiet, comfortable operating environment.
Palm command Proportional Pressure Control
(PPC)
PPC-controlled palm command joystick provides blade
control. Combined with the highly reliable Komatsu
hydraulic system, precise control is the result.
Closed-center Load Sensing System (CLSS)
hydraulic system
With CLSS hydraulics, blade lever stroke is directly
proportional to blade speed, regardless of the load and
travel speed. This results in superb fine controllability.
Palm Command Control System (PCCS)
The low-effort PCCS joystick controls all directional
movements including machine travel speed as well as
counter-rotation.
Spring
Silicon oil
Rubber
Boot
RH
Down Shift
Up Shift
F
R
LH
Heavy-duty undercarriage
Large link, large bushing diameter, and wider sprocket teeth
extend undercarriage life.
Protected travel motors and final drives
Travel motors and final drives are mounted within the track
shoe width for protection from rocks and stumps, and for
improving durability.
Monocoque track frame
Komatsu’s monocoque track frame design using thicker box
section material and fewer welded components provides
increased rigidity and strength.
One-piece nose guard
Simplified high-rigidity structure with thicker plates reduces
vibration and noise.
Main frame
High-rigidity simple main frame structure combined with
thick plates and steel castings provide increased reliability
and durability.
Modular design
One of the design goals behind the creation of the D39 was
to manufacture a more durable machine. This was achieved
by reducing component complexity and using a strong
modular design for increased serviceability and durability.
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Photo may include optional equipment.
Photo may include optional equipment.
Motor cover
Motor cover
