AIR BRAKE SYSTEM
SERVICE BRAKES.
Air operated service brakes are provided on 8 wheels with pressure supplied by an engine mounted 12
CFM compressor. Normal operating air pressure is between 95 and 125 psi. If tank pressure drops below 70 psi,
the low pressure warning buzzer will operate indicating approach of an unsafe braking condition and automatic
application of the spring brakes.
PARKING AND AUTOMATIC SPRING BRAKES.
Both rear axles are equipped with automatic spring brakes which are held in the released position by air
pressure. These also serve as parking brakes. Normal operation for parking is accomplished by pulling up on the
parking brake knob and pushing down to release. Do NOT use for stopping vehicle except in case of emergency
as a severe sudden stop will result. An auxiliary air supply tank is provided for brake release if towing operation
might be required. Mechanical release is also possible. Refer to Component Manufacturer's Manual for details.
BRAKE OPERATION SERVICE BRAKES.
For most effective braking and for maximum life from brake system components, the following
suggestions are made:
Air brakes have light pedal operation and the driver is cautioned to use extreme care in application until a
good "feel" is achieved.
Use the engine as a brake when approaching a stop or when going down a long grade. On a downgrade,
use the same transmission gear as would be needed to go up the same grade. DO NOT ALLOW ENGINE TO
EXCEED GOVERNED SPEED.
When necessary to use brakes to reduce vehicle speed on a
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