Paccar PX-9 Operator's Manual - page 54
OPERATING INSTRUCTIONS
If the vehicle drive wheels begin to skid
or if there is a fishtailing motion, DO
NOT activate the engine brakes.
If traction is maintained using the
retarding power of the engine alone
and more braking power is required,
switch the two-position selector switch
to the “LOW” position and activate
the engine brakes by switching the
“ON/OFF” switch to the “ON” position.
If the vehicle’s drive wheels begin to
skid or there is a fishtailing motion,
switch the “ON/OFF” switch to the
“OFF” position.
If traction is maintained when the
engine brakes are activated and more
braking power is required, move the
two-position selector switch to the “HI”
position.
Again, if the vehicle has lost traction or
if there is a fishtailing motion, switch
the “ON/OFF” switch to the “OFF”
position. DO NOT attempt to use the
engine brakes in the “HI” position.
4-18
Y53-1185-1B1
(12/2014)
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