Daimler Freightliner Cascadia 2021, Driver Manual

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General Information, Allison
Transmissions
Allison transmissions have electronic shift controls
that can be programmed to allow the use of different
numbers of geared speeds. For instance, the trans-
mission can be programmed to operate as a
4-speed, 5-speed, or 6-speed unit in the "primary"
shift mode. If needed, a "secondary" shift mode can
be programmed to provide another shift configuration
to optimize vehicle use under different operating con-
ditions. To activate a secondary shift mode, or other
special functions programmed into the electronic con-
trol unit (ECU), briefly depress the mode switch on
the multi-function stalk switch control; see
Fig. 17.1 ,
item 3.
These transmissions use the multi-function stalk
switch to select mode, direction, neutral, low, and to
preselect lower ranges. The current gear, highest
available gear, and mode are shown in the driver dis-
play; see
Fig. 17.11 . Forward shifts can be made
either automatically or by using Manual mode.
Operation Tips, Allison Transmissions
WARNING
Never shift from neutral (N) to drive (D) or re-
verse (R) at engine speeds above idle. The ve-
hicle will lurch forward or backward, which could
cause property damage and personal injury.
NOTICE
The engine should never be operated for more
than thirty seconds at full throttle with the trans-
mission in gear and the output stalled. Prolonged
operation of this type will overheat the transmis-
sion fluid and will result in severe damage to the
transmission.
NOTICE
Do not allow the vehicle to coast in neutral. This
can result in severe transmission damage. Also,
no engine braking is available.
The following tips highlight important operation prin-
ciples.
•
Use reverse (R) to back the vehicle. Com-
pletely stop the vehicle before shifting from a
forward gear to reverse, or from reverse to for-
ward.
•
Select drive (D) for all normal driving condi-
tions. The vehicle will start out in 1st gear (un-
less the transmission is programmed with 2nd
gear start), and as speed increases, the trans-
mission will upshift through each gear auto-
matically. As the vehicle slows down, the trans-
mission will downshift to the correct gear
automatically.
•
The pressure of your foot on the accelerator
pedal influences the automatic shifting. When
the pedal is fully depressed, the transmission
will automatically upshift at higher engine
speeds. A partially-depressed position of the
pedal will cause the upshifts to occur at a
lower engine speed.
f611803 10/21/2019
Fig. 17.10, Eaton Transmission Prognostics
1. Current Gear
2. Highest Gear
Available
3. Mode
Fig. 17.11, Allison Gear Display in Automatic Mode
Automated and Automatic Transmissions
17.11