COMMON AR 3479535 - Caterpillar

Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.To prevent possible injury, perform the procedure that follows before testing and adjusting the brake system.
Move the machine to a smooth horizontal location. Move away from any machines that are working and any personnel.
Move the transmission control to the NEUTRAL position. Stop the engine.
Permit only one operator on the machine. Either keep other personnel away from the machine, or keep other personnel in the sight of the operator.
Activate the parking brakes.
Install the steering frame locks. Refer to Operation and Maintenance Manual, SEBU7064, "Safety Section".
Place blocks in front of the wheels and behind the wheels.
Illustration 1 g00820417
Dump Body Prop
Raise the body of the truck enough to lift the body prop and then move the hoist control to the HOLD position. Install the dump body prop in order to support the dump body. Move the hoist control to the FLOAT position. This will allow the body to lower slowly until the weight of the body is supported by the body prop.Note: The body must be empty.
Make sure that all oil pressure is released before any fittings, hoses or components are worked on.
Push on the brake pedal many times until there is no brake oil pressure.
Move the parking brake to the ENGAGED position.Note: The troubleshooting for the braking system in this section deals with the service brakes and the parking brake. The hydraulic system involves the operation of the torque converter, the brakes, the brake cooling, and the hoist. Refer to Steering, Suspension and Body Hoist System, RENR3400, "Testing And Adjusting".Visual checks are the first steps in order to troubleshoot a problem. The visual checks find the problems that can be quickly corrected. If the visual checks do not show any problems, the operational checks are the next steps. The operational checks permit the identification of possible problems with the machine during operation.