Allison Transmission 3000 MH Series, Руководство оператора

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USING THE ENGINE TO SLOW THE VEHICLE
WARNING: To avoid loss of control, use a combination of
downshifting, braking, and other retarding devices. Downshifting to a
lower transmission range increases engine braking and can help you
maintain control. The transmission has a feature to prevent automatic
upshifting above the lower range selected. However, during downhill
operation, if engine governed speed is exceeded in the lower range, the
transmission will upshift to the next higher range to prevent engine
damage. This will reduce engine braking and could cause a loss of
control. Apply the vehicle brakes or other retarding device to prevent
exceeding engine governed speed in the lower range selected.
Engine braking provides good speed control for going down grades. When the
vehicle is heavily loaded, or the grade is steep, it may be desirable to preselect a
lower range before reaching the grade. If engine-governed speed is exceeded, the
transmission will upshift automatically to the next range.
To use the engine as a braking force, select the next lower range. If the vehicle is
exceeding the maximum speed for this range, use the service brakes and/or
retarder to slow the vehicle. When a lower speed is reached, the TCM/ECU will
automatically downshift the transmission.
USING THE HYDRAULIC RETARDER
WARNING: DO NOT USE THE RETARDER DURING INCLEMENT
WEATHER OR WHEN ROAD SURFACES ARE SLIPPERY.
De-energize the retarder at the master control switch.
To help avoid injury or property damage caused by loss of vehicle
control, be ready to apply vehicle brakes or other retarding device if the
transmission retarder does not apply. If a retarder is present but is not
detected by “autodetect”, the retarder will not function. Be sure to check
for proper retarder function periodically. Whenever the retarder does not
apply, seek service help immediately.
On vehicles which have the primary retarder control based upon closed
throttle position, brake pedal position, or brake apply pressure, always
manually disable the retarder controls during inclement weather or
slippery road conditions.
Regardless of the type of Allison retarder controls on your vehicle, the following
safety features are common to each con
fi guration:
•
The retarder can be disabled when inclement weather or slippery road
conditions are present.
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