freightliner 108SD, Driver Manual

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Low
Low (L) is located at the lower end of the four-
position gear selector switch on the SmartShift con-
trol lever. To select L, press in the neutral lock button
and move the gear selector switch to the position
below D.
When in low, the current gear is maintained. Re-
quests to upshift are not enabled.
IMPORTANT: If the engine is approaching over-
speed, the TCU will override the current gear
setting and upshift to prevent engine damage.
To enhance engine braking, downshifts are per-
formed at higher rpm than normal.
If L is selected from neutral while stopped, the ve-
hicle starts up in first gear and stays there until the
engine approaches overspeed.
Upshifting
To request an upshift with the transmission in drive,
pull the control lever up (towards the driver). If the
gear is available, the transmission will upshift and the
new gear will display on the gear indicator. Skip
shifts are not available while upshifting. Upshifts are
not available in low, except to prevent engine over-
speed.
If the transmission does not upshift quickly enough
after power up or a load change, begin the shift
manually. The TCU will learn the new load-based
shift conditions after three or four shifts.
If the gear requested is unavailable, a tone will
sound. An unavailable request to upshift is not stored
in memory; the upshift must be requested again.
Downshifting
To request a downshift with the transmission in drive
or low, push the control lever down (away from the
driver). If the gear is available, the transmission will
downshift and the new gear will display on the gear
indicator. Skip shifts are available while downshifting.
For best engine braking, select low while moving. In
low, downshifts are performed at higher rpm than in
drive.
IMPORTANT: If the engine is approaching over-
speed, the TCU will override the current gear
setting and upshift to prevent engine damage.
If the gear requested is unavailable, a tone will
sound. An unavailable request to downshift is not
stored in memory; the downshift must be requested
again.
When coasting to a stop, the TCU may not finish the
downshift until the driver presses down on the
throttle pedal again.
IMPORTANT: A downshift request can never
result in a shift into neutral, even if the vehicle is
in the drive position in the lowest possible gear.
Before starting down a hill, slow down. Downshift to
a speed that you can control without hard pressure
on the service brakes.
Before entering a curve, slow down to a safe speed.
Downshift if necessary. This lets you use some
power through the curve to help the vehicle be more
stable on the turn. It also allows you to regain speed
faster as you come out of the curve.
Ultrashift Diagnostics
Clutch Protection Fault
Even though a vehicle with an UltraShift transmission
does not have a clutch pedal, it does have a me-
chanical clutch. As you slowly increase and decrease
engine rpm from a stop, the mechanical clutch is en-
gaging and disengaging, just like slipping the clutch
with a manual transmission. Excessive clutch slip-
page creates heat and reduces the life of the clutch.
These are some conditions which can cause clutch
damage:
10/14/2003 f610681
Fig. 14.6, Gear Indicator: Reverse Low Gear
Automated and Automatic Transmissions
14.5