freightliner 108SD, Driver Manual

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Operation, UltraShift Transmissions
Automatic and Manual Modes
The SmartShift control lever has a slide switch lo-
cated on the body of the control lever just before the
paddle widens out. See
Fig. 14.2 . The slide switch
controls the forward driving mode, automatic (AUTO)
or manual (MAN).
To change mode at any time, move the slide switch
in the desired direction. This allows the driver to re-
spond to a wide range of driving conditions, such as
blind corners, tight curves, and steep hills.
IMPORTANT: In either mode, it is possible to
shift manually by moving the lever up or down
as needed. When the engine speed is within 75
rpm of the load-based shift point for an auto-
matic shift, the TCU will advance the shift.
In either mode, the gear indicator displays the cur-
rent gear. See
Fig. 14.3 .
At the start of a shift, the current gear continues to
display until the transmission has been pulled into
neutral. As the transmission is synchronizing for the
new (target) gear, the gear indicator flashes the num-
ber of the target gear.
When the shift is complete, the gear indicator dis-
plays the new gear, without flashing.
Automatic Mode (AUTO)
In automatic drive mode (AUTO), upshifts and down-
shifts are made by the transmission without driver
intervention. Press the neutral lock button, move the
gear selector switch to drive (D), and press down on
the throttle pedal. The transmission will shift auto-
matically.
If driving conditions require, it is still possible to re-
quest a manual shift. The transmission will make the
shift if the engine speed is within 75 rpm of the load-
based shift point for that gear.
If the driver presses down on the throttle pedal after
a manual downshift in automatic mode, the transmis-
sion will upshift again if the TCU requires it.
Manual Mode (MAN)
In manual drive mode (MAN), upshifts and down-
shifts are made by the driver.
•
To upshift, pull the lever up (towards the
driver).
•
To downshift, push the lever down (away from
the driver).
The system will hold the current gear until the driver
requests a shift. In downhill situations in particular,
the driver must be alert to vehicle speed by down-
shifting and/or using the service brakes as needed.
A shift request will be refused if the selected gear
would cause engine overspeed or excessive lugging.
01/21/2004 f270079c
1
2
3
1. Driving Mode Slide
Switch 2. Gear Selector Switch
3. Neutral Lock Button
Fig. 14.2, Shift Controls and Indicators, UltraShift and
AutoShift Transmissions
10/13/2003 f610680
NOTE: The gear indicator displays the current gear. In
this example, it displays first gear.
Fig. 14.3, Gear Indicator: Current Gear
Automated and Automatic Transmissions
14.2