freightliner M2 Plus 2023 Manual page 182

Automated and Automatic Transmissions
•
The TCM will prevent shifts from park or
neutral to range when auxiliary equipment,
such as a power takeoff unit (PTO), is in
operation.
Operating Instructions, On-Highway
Transmissions
Allison automatic transmissions are electronically
controlled. The shift selector provides five or six
forward ranges and one reverse range.
P (Park, optional on 1000 and 2400
Series)
Use park when turning the engine on or off, to check
vehicle accessories, to operate the engine in idle for
longer than 5 minutes, and for stationary operation of
the power takeoff, if equipped. This position places
the transmission in neutral and engages the park
pawl of the transmission.
NOTE: This does not apply the parking brake.
PB (Auto-Apply Parking Brake, optional
on 2000 Series)
WARNING
Before selecting PB on the shift lever, make sure
the ignition switch is not in the OFF position.
Selecting PB with the ignition switch in the OFF
position places the transmission in neutral, but
does not apply the parking brake automatically.
The vehicle could roll unexpectedly, possibly
causing property damage or personal injury.
The auto-apply parking brake places the
transmission in neutral and applies the parking
brake.
NOTE: Selecting PB on the shift lever does not
engage the park pawl of the transmission.
R (Reverse)
Reverse is used to back the vehicle. When the
selector is in reverse, the reverse warning signal will
sound. Always bring the vehicle to a complete stop
before shifting from a forward range to reverse, or
from reverse to a forward range.
14.17
NOTICE
Extended idling in reverse may cause
transmission overheating and damage.
Do not idle in reverse for more than 5 minutes.
Select P (park), PB (auto-apply parking brake), or N
(neutral) when time at idle exceeds 5 minutes.
NOTE: The shift into reverse may not succeed if
a range inhibitor is active. Check for illumination
of the RANGE INHIBIT indicator.
N (Neutral)
The neutral position places the transmission in
neutral. This position is used when starting the
engine and for stationary operation.
WARNING
Failure to apply the vehicle parking brakes when
the transmission is in neutral may allow the
vehicle to move unexpectedly, possibly causing
property damage or personal injury.
When neutral is selected, the vehicle service brakes,
parking brake, or emergency brake must be applied.
Selecting neutral does not apply vehicle brakes
unless an auxiliary system to apply the parking brake
is installed.
WARNING
Do not coast in neutral. Coasting in neutral can
cause an accident, possibly resulting in severe
personal injury or death.
Do not let the vehicle coast in neutral. If the vehicle
is allowed to coast in neutral, the engine brake will
not work and you could lose control of the vehicle.
NOTICE
Coasting in neutral can cause severe
transmission damage.
D (Drive)
WARNING
When going downhill, use a combination of
downshifting, braking, and other retarding
devices to control vehicle speed and the engine's
rated governed speed. Failure to do so could