Paccar TX-8, Руководство оператора

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NOTE
If Auto-park has been activated, the
transmission will not exit Park (
P ) until
the shifter is first moved to P before
selecting another transmission mode.
Engine Overspeed and
Underspeed Protection
The transmission system will upshift, if
necessary, to prevent damage during an
engine overspeed condition and will also
downshift to prevent engine lug (driving in
a high gear at low rpm) and a potential stall
during an engine underspeed condition.
Engine Overspeed Protection is active in
Drive (
D ), Manual, and LOW modes;
however, Engine Underspeed Protection is
only active when in Drive (
D ) mode or
Manual mode.
Hill Start Aid (option)
Hill Start Aid prevents unwanted vehicle
movement on steep grades when
transitioning from the brake to throttle
pedal. Hill Start Aid can be disabled using
the Hill Start Aid Disable switch (see
Hill
Start Aid Disable Switch ).
Hill Start Aid activates by default on a road
grade of 3% and whenever Neutral Idle
Control Plus (NIC+) is active.
LOW Mode
LOW mode should be used any time you
want to limit upshifting, hold lower gears, or
improve engine braking through lower gear
selection. For example, when driving down
long grades or when coming to a stop.
• Selects lowest available gear for
start gear. The starting gear cannot
be changed in LOW mode.
NOTE
If the driver attempts to select a non-
neutral mode without applying the
service brake, the transmission will not
shift into gear. If this is attempted, the
driver will need to re-select Neutral (
N )
and then press the service brake be-
fore a new mode can be selected.
• If LOW is selected while moving,
the transmission will not upshift
(except in conditions requiring
overspeed protection – see
Engine
Overspeed and Underspeed
Protection
on page 14). The
transmission system will downshift
at the earliest opportunity to enable
higher than normal engine RPM to
provide maximum engine braking.
WARNING
On slippery surfaces minimize engine
braking in LOW mode. Excessive en-
gine braking at higher engine RPM
could cause a loss of traction and vehi-
cle control.
NOTE
This transmission initiates upshifts
from Drive (
D ), Manual, and LOW
modes for engine overspeed protec-
tion.
FEATURES - Engine Overspeed and Underspeed Protection
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