Operating Instructions
PACCAR
Y53-1030A 12/09
– 29 –
WARNING! The exhaust brake is not intended as
the primary brake for the vehicle, nor is it an
emergency brake. The service brakes must be
used in an emergency. Relying solely on the
exhaust brake to stop the vehicle in an emer-
gency could cause an accident and lead to per-
sonal injury. The exhaust brake only helps the
service brakes by using pressure to slow the
drive train. You must use the service brakes for
quick or emergency stops.
WARNING! Do not use the exhaust brake when
operating on surface with poor traction (such as
wet, icy or
snow covered roads). Retarders can
cause the wheels to skid on a slippery surface.
You could lose control of the vehicle and jack-
nife if the wheels begin to skid, resulting in an
accident.
WARNING! Do not use an exhaust brake when
driving bobtail or with an unloaded trailer. There
may not be enough weight on the rear axle to
provide traction. This could cause a lose of con-
trol and jackknife resulting in an injury accident.
Make sure the exhaust brake is switched OFF
when bobtailing or with an unloaded trailer.
When the engine (VGT) exhaust brake switch is in the
ON
position, the engine's electronic control module (ECM)
monitors inputs (such as accelerator pedal position and
engine speed). From these inputs, the ECM determines
when to enable the engine (VGT) exhaust brake feature
when the proper braking conditions are present.
Other features/switches like cruise control, can also affect
when the engine (VGT) exhaust brake activates. For more
infor mation on how the engine (VGT) exhaust brake
functions, refer to vehicle operation manual or contact a
PACCAR Authorized Repair Location.
WARNING! To reduce the possibility of personal
injury or property damage, always be prepared
to use the vehicle service brakes for emergency
stopping. The safe control speed of a vehicle will
vary with the size of the load, the type of load,
the grade, and the road conditions.
NOTE: The exhaust brake can only be activated
when the accelerator pedal is at its low idle position.
With the throttle at low idle position, fueling com-
mands to the cylinders will not detract from the brak-
ing power of the brake system.
NOTE: The engine (VGT) exhaust brake is designed
to assist the vehicle's service brakes when slowing
the vehicle to a stop.
Summary of Contents for PX 8
Page 1: ......
Page 2: ......
Page 3: ...Y53 1030A 12 09 Operator s Manual ...
Page 6: ...Foreword ...
Page 16: ...Introduction 10 Y53 1030A 12 09 PACCAR ...
Page 50: ...Operating Instructions 44 Y53 1030A 12 09 PACCAR ...
Page 58: ...Maintenance Guidelines 52 Y53 1030A 12 09 PACCAR ...
Page 60: ...Service Literature 54 Y53 1030A 12 09 PACCAR ...
Page 78: ...Maintenance Specifications 72 Y53 1030A 12 09 PACCAR ...
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