Komatsu GD555-5 Operation & Maintenance Manual page 164

OPERATION
SHIFTING GEAR ON MACHINE
Avoid sudden gear shifts when traveling at high speeds. Before shifting down the gear, apply the brake to reduce the travel
speed.
Do not set the gear shift lever to the N (Neutral) position when traveling or going downhill. The braking force of the engine
cannot be applied and there is danger of unexpected accidents. Be sure to travel by keeping the gear shift lever placed in any
of the gear speed positions.
NOTICE
When shifting gears, always shift 1 gear at a time.
When operating gear shift lever (1), place it securely in each position.
When moving gear shift lever (1) from N (NEUTRAL) to R (REVERSE) or
F (FORWARD), release accelerator pedal (2) and operate the lever
during low idle of the engine.
Do not depress inching pedal (3) during gear shifts.
When shifting gear, do as follows.
INCREASE SPEED
Loosen the depression of accelerator pedal (2) and set gear shift
lever (1) up to the next gear speed.
REDUCING SPEED
Release accelerator pedal (2) to reduce the engine speed and set
gear shift lever (1) down to the next gear speed.
REMARK
An abrupt downshift operation (shifting down to the gear speed
following the next one or farther at a time) probably actuates the
function of preventing the engine from overrunning.
If this function starts, it is necessary to wait for the downshift to the
desired gear speed through travel speed reduction by using the
brake or naturally, because the desired gear speed is not obtained
until the machine slows down to a certain travel speed.
WARNING
OPERATION
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