Komatsu GD555-5 Operation & Maintenance Manual page 232

OPERATION
When moving a failed machine on a downhill slope, a larger towing machine must be used to ensure ample
control and braking power. Another method is to use a second towing machine at the rear of the failed machine.
In this way, it is possible to prevent the failed machine from going out of control and turning over.
It is impossible to determine the drawbar pull needed for various conditions. The minimum drawbar pull may be
sufficient on horizontal, flat ground, but the maximum drawbar pull is needed on slopes or on rough roads.
When towing a failed machine, please contact your Komatsu distributor.
METHOD OF RELEASING PARKING BRAKE
When releasing the parking brake, stop the machine on level ground and check that the surrounding area is safe. If it is
necessary to release the brake on a slope in an emergency, block the tires before starting the operation.
If the parking brake is released, the brake cannot be used, so check the safety carefully when moving the machine.
If the engine will not run for some reason, use the following methods to release the parking brake and tow the
machine.
1. Turn to remove cover plug (2) of parking brake (1) on the front
side of the final drive case.
2. Loosen adjustment bolt (4) and locknut (3) inside the spring
chamber until a clearance is formed between the disc and pad.
Lock nut (3): Width across flats; 20.8 mm (0.8 in)
Adjustment bolt (4): Width across flats of hexagonal socket;
8.1 mm (0.319 in)
3. This will release parking brake (1).
NOTICE
After releasing the parking brake and moving the machine, it is necessary to adjust the parking brake again. Please contact your
Komatsu distributor to have the parking brake adjusted.
WARNING
TROUBLESHOOTING
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