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CAUTION:
If you apply any one of the air brake parking
controls while the vehicle is moving, your rig will
stop suddenly. If you are not ready for this, you
or others could be injured. Don’t apply any one
of these controls while you’re driving, unless you
have to make an emergency stop.
If the air pressure drops below 60 to 70 psi (413 to
482 kPa), the primary brake light and warning buzzer
will come on. If the air pressure drops to 35 to 45 psi
(241 to 310 kPa), the red trailer air supply knob will
automatically pop out and apply the spring brakes on
the trailer.
If the air pressure drops to 35 to 45 psi (241 to 310 kPa),
the yellow park brake knob will automatically pop out
and apply the spring brakes on the truck or tractor.
If you ever have a complete loss of air so that your air
brakes automatically apply, there is a way that the tow
operator can release the parking brakes to tow the
vehicle. See “Towing Your Vehicle” in the Index.
CAUTION:
If your vehicle is left in gear, the engine can start
if the vehicle starts to roll. This can easily happen
if you have the diesel engine. Shift the
transmission into NEUTRAL (N) before you
leave the vehicle.
Summary of Contents for 2003 C4C042
Page 1: ......
Page 6: ...v Here are some examples of symbols you may find on your vehicle ...
Page 66: ...1 59 United States Canada ...
Page 143: ...2 68 The Instrument Panel Your Information System ...
Page 302: ...6 48 Single Axle Models ...
Page 329: ...6 75 GM Vehicle Care Appearance Materials ...
Page 377: ...7 31 Maintenance Record DATE ODOMETER READING SERVICED BY MAINTENANCE PERFORMED ...
Page 378: ...7 32 Maintenance Record DATE ODOMETER READING SERVICED BY MAINTENANCE PERFORMED ...
Page 379: ...7 33 Maintenance Record DATE ODOMETER READING SERVICED BY MAINTENANCE PERFORMED ...
Page 380: ...7 34 Maintenance Record DATE ODOMETER READING SERVICED BY MAINTENANCE PERFORMED ...