Paccar PX-9 Operator's Manual - page 30
OPERATING INSTRUCTIONS
NOTE
The engine (VGT) exhaust brake
is designed to assist the vehicle's
service brakes when slowing the
vehicle to a stop.
Vehicle service brakes must always be
used. The engine brake is not intended
to be used as the primary brake of the
vehicle, nor is it an emergency brake.
The engine retarder only helps the
service brakes by using pressure to
slow the drivetrain. Use the service
brakes for quick stops.
CAUTION
Exceeding governed engine speed
can cause engine damage. Oper-
ating the engine beyond the maxi-
mum engine speed may cause se-
rious engine damage and is con-
sidered engine abuse. Use the en-
gine and vehicle braking systems
to control engine speed.
The optimum braking power of the
engine (VGT) exhaust brake is reached
at rated engine speed. Correct gear
selection, therefore, is critical.
Typically, on vehicles equipped with
automatic transmissions, the engine
electronic control module (ECM) and
the transmission will determine the
correct gear selection.
3-10
Y53-1185-1B1
(12/2014)
3