R
ELIABILITY
F
EATURES
E
ASY
M
AINTENANCE
8
OFF-HIGHWAY TRUCK
HD405
-7
O
F F
- H
I G H W A Y
T
R U C K
High-rigidity frame
Cast-steel components are used in the
main frame for high-
stress areas where
loads and shocks are
most con-
centrated.
Komatsu components
Komatsu manufactures the engine, torque converter,
transmission, hydraulic units, and electrical parts on this
dump truck. Komatsu dump trucks are manufactured with an
integrated production system under a strict quality control
system.
Rigorous dump body design
The standard dump body is made of
160 kg/mm
2
227,520 PSI
high-tensile-strength steel for excellent rigidity and reduced
maintenance cost. The V-
shape design also
increases structural strength.
The side and bottom plates of
the dump section are rein-
forced with ribs for added
strength.
Reliable hydraulic system
The oil cooler is installed in the radiator lower tank, improv-
ing the reliability of the hydraulic system during sudden tem-
perature rises. Further, in addition to the main filter, a 25-
micron line filter is at the entrance to the transmission con-
trol valve. This system helps to prevent secondary faults.
Sealed DT connectors
Main harnesses and
controller connectors are
equipped with sealed DT
connectors providing high
reliability, water resistance
and dust resistance.
ABS (Antilock braking system)
(Option)
Using its outstanding electronics technology, Komatsu is
the first in the industry to introduce ABS on construction
machinery. This system prevents the tires from locking,
thus minimizes skidding under slippery conditions while
applying the service brake.
ASR (Automatic spin regulator)
(Option)
ASR automatically prevents the rear tires on either side
from slipping on soft ground for optimal traction.
Protection functions supported by electronic control
Item
Function
Downshift inhibitor
Over-run inhibitor
Reverse inhibitor
Forward/Reverse shift inhibitor
Anti-hunting system
Neutral safety
Even if the driver downshifts accidentally,a speed appropriate to the current gear is automatically set,preventing over-runs.
When descending grades, if the vehicle's speed surpasses the maximum for the current gear,
the rear brakes automatically operate, preventing over-runs.
The vehicle is prevented from moving backward when operating the body.
This device makes it impossible to shift from forward to reverse when the vehicle's speed surpasses 4 km/hour.
When running near a shift point, smooth automatic shifting takes place.
The engine is prevented from starting when the shift lever is not in neutral.
Flat face-to-face O-ring
seals are used to securely
seal all hydraulic hose
connections and to prevent
oil leakage.
Flat face-to-face O-ring seals
Advanced monitoring system
Extended oil change intervals
In order to minimize operating costs, oil change intervals
have been extended:
●
Engine oil 500 hours
●
Hydraulic oil 4000 hours
Centralized greasing
points
(Option)
Greasing points are central-
ized at three locations.
Flange type rim
Flange type rims provide
easy removal/installation for
the tires.
Electric circuit breaker
A circuit breaker is adopted in
important electric circuits that
should be restored in a short
time when a problem occurs
in the electrical system.
Brake cooling oil recovery tank
To protect environment, a tank is installed to recover brake
cooling oil in the event of brake floating seal leakage.
Pedal-operated secondary brake
If there should be a failure in the foot brake, the parking
brake and front disc brakes
are activated as pedal operat-
ed secondary brake. In addi-
tion, when hydraulic pressure
drops below the rated level,
the parking brake is automati-
cally actuated.
Lead-free radiator
In addition to compliance with emission regulations, a lead-
free aluminum core is adopted for the radiator to comply
with global environmental requirements.
The Komatsu advanced monitoring system identifies main-
tenance items, reduces diagnostic times, indicates oil and
filter replacement hours and displays abnormality codes.
This monitor system helps to maximize machine production
time.
Wet multi-disc brakes and fully hydraulic braking
systems
mean lower maintenance costs and higher relia-
bility. Wet disc brakes are fully sealed to keep contaminants
out, reducing wear and maintenance. Brakes require no
adjustments for wear, meaning even lower maintenance.
Added reliability is designed into the braking system by the
use of three independent hydraulic circuits providing
hydraulic backup should one of the circuits fail. Fully
hydraulic braking systems eliminate the air system so air
bleeding is not required, and water condensation that can
lead to contamination, corrosion and freezing is eliminated.
O-ring
Nipple
Hose
Centralized arrangement of filters
The filters are centralized so that they can be
serviced easily.
9
HD405
-7