SRT45 Off-Highway Truck
3-30
Safety, Operation and Maintenance Manual
However, when stopped for a more extended
period with the engine left running, shift the
transmission to neutral to avoid unnecessary
heat buildup and apply the parking brake.
WARNING
Always select Neutral and apply the
parking brake before leaving the
operator’s seat.
(4) Mode selection switch - Gives the option
to select between transmission 'POWER' and
'ECONOMY' shift schedules.
Note:
The transmission must be in neutral
before the switch will function; otherwise,this
practice can result in transmission damage.
The transmission torque converter is equipped
with a lockup clutch which, when engaged
by the ECU, locks the converter pump and
turbine together as a single unit and allows
power to be transmitted mechanically from
the engine directly to the transmission gearing
on a 1 to 1 ratio. When the lockup clutch is
disengaged, the torque converter acts as a
uid coupling, multiplying torque when engine
speed is signicantly higher than transmission
output shaft speed.
When the mode selection switch is in the
'POWER' position, the ECU controls operation
of the lockup clutch according to signals
received by the throttle position sensor (giving
engine speed as a percent of throttle), the
transmission output shaft speed sensor,
and range selector. The ECU may delay
application of the lockup clutch and allow
torque multiplication by the torque converter to
take place until a balance is achieved between
engine speed and transmission output shaft
speed before activating the lockup clutch.
Power versus Economy Mode
T h e P O W E R m o d e i s d e s i g n e d f o r
applications involving heavy loads and hilly
Controls and Operating
To Next Page
Loading...