Komatsu GD555-5 Operation & Maintenance Manual page 92

OPERATION
TRANSMISSION MODE SELECTOR SWITCH
When switching from torque converter Auto mode to Manual mode, set the gear shift lever to N (NEUTRAL) position while the
machine stops, set the engine to low idle, and then switch over.
When starting the machine off after switching over the mode, observe the items in "MOVING MACHINE OFF (FORWARD,
REVERSE, SHIFTING GEAR), STOPPING (PAGE 3-108)".
This model has a TORQFLOW transmission with lockup clutch.
By using this switch (8), changeover between torque converter Auto mode and Manual mode can be carried out.
While selecting torque converter Auto mode, machine operations are easier and the automatic gear shift is also
available.
Position (A) (T/C AUTO): Torque converter Auto mode
When carrying out work as the easy-to-operate torque converter
machine with automatic transmission functions, select torque
converter Auto mode. At F5 or higher gear speeds, the gear shift
is automatically operated in lockup state which has high
transmission efficiency.
Inching operations are not necessary, and operations of only the
brake pedal and accelerator pedal enable the optimum work.
Torque converter Auto mode is suitable for the following works:
Work during which loads fluctuate widely and the engine speed
is significantly lowered
Snow clearing work or any other work carried out at F5 or higher
gear speeds
Long distance travel
Work carried out at very low speeds
Position (B) (MANU): Manual mode
When carrying out work with the same operating feeling as the
conventional direct power shift (hydroshift), select Manual mode.
CAUTION
EXPLANATION OF COMPONENTS
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