Paccar PX-9 Operator's Manual - page 28
OPERATING INSTRUCTIONS
function is controlled by a switch
located on the dash of the vehicle.
The engine (VGT) exhaust brake
works by retarding engine speed by
creating high exhaust back pressure.
This back pressure is obtained by
restricting airflow through the turbine
housing of the turbocharger. This
restriction through the turbine housing
is created through positioning of the
sliding nozzle (1) located internally
to the turbocharger. The position of
the sliding nozzle is controlled by
the engine electronic control module
(ECM). This option may not be
available on your vehicle.
WARNING!
The exhaust brake is not intended
as the primary brake for the vehi-
cle, nor is it an emergency brake.
The service brakes must be used
in an emergency. Relying solely on
the exhaust brake to stop the ve-
hicle in an emergency could cause
an accident and lead to personal
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. Fail-
ure to comply may result in death,
personal injury, equipment or prop-
erty damage.
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 jacknife if
the wheels begin to skid, resulting
in an accident.
Failure to com-
ply may result in death, personal
injury, equipment or property dam-
age.
3-8
Y53-1185-1B1
(12/2014)
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