Driving Precautions; Allison On-Highway Transmissions - freightliner S2 Operator's Manual

Transmission

Driving Precautions

The vehicle operator should use care when acceler-
ating or downshifting on slippery road surfaces. Sud-
den acceleration or engine braking, caused by shift-
ing to a lower gear range, can result in a loss of
vehicle control. This is very important on snow or ice
covered roads. See Chapter 13
brake operation.
If the vehicle is stuck in sand or mud, do not attempt
to pull the vehicle out under its own power. Request
professional towing assistance.
NOTICE
Do not attempt to rock the vehicle. If rocking the
vehicle is necessary, even at low speeds, it may
cause engine overheating, axle damage, trans-
mission damage or failure, or tire damage.
Do not coast the vehicle in neutral. Severe trans-
mission damage may result and the vehicle will
not have the benefit of engine braking.
WARNING
To reduce the risk of personal injury, before
going down a steep or long grade, reduce speed
and downshift the transmission. Do not hold the
brake pedal down too long or too often while
going down a steep or long grade. This could
cause the brakes to overheat, reducing their ef-
fectiveness. As a result, the vehicle will not slow
down at the usual rate. Failure to take these
steps could result in loss of vehicle control.
To avoid skidding on slippery roads, do not downshift
into L (low) at speeds above 20 mph (32 km/h).
On slippery surfaces, avoid quick movements of the
steering wheel. Decrease speed and allow for extra
stopping distance required by these conditions. For
non-ABS brakes, apply the brakes by pumping the
pedal steadily and evenly to avoid wheel lock-up and
loss of vehicle control.
Avoid driving through flooded areas unless you are
sure the water is no higher than the bottom of the
wheel rims. Drive through slowly. Allow adequate
stopping distance since wet brakes do not grip well.
After driving through water, gently apply the brakes
several times while the vehicle is moving slowly to
dry the brakes.
10.1
for information on
When driving on icy or graveled surfaces, reduce
speed. Avoid sharp turning maneuvers.
Allison On-Highway
Transmissions
The Allison on-highway transmissions are fully auto-
matic and include the 2100 Series, 2200 Series,
2350 Series, 2500 Series, and 3000 Series. Refer to
www.allisontransmission.com
mation.
Safety Precautions
2000 Series
WARNING
Do not leave the vehicle unattended with the en-
gine running. If you leave the vehicle and the en-
gine is running, the vehicle can move suddenly,
which could result in personal injury or property
damage.
On vehicles with Allison 2000 series transmissions,
do the following steps if you have to leave the ve-
hicle with the engine running (for example, when
checking the transmission fluid).
Without Auto-Apply Parking Brake
1. Bring the vehicle to a complete stop using the
service brake.
2. Ensure that the engine is at low idle rpm.
3. Put the transmission in neutral.
4. Apply the parking brake, and make sure it is
properly engaged.
5. Chock the rear tires and take any other steps
necessary to keep the vehicle from moving.
With Auto-Apply Parking Brake
1. Bring the vehicle to a complete stop using the
service brake.
2.
Ensure that the engine is at low idle rpm.
3. Put the transmission in PB (auto-apply parking
brake).
4. Apply the parking brake (if so equipped), and
make sure it is properly engaged.
for additional infor-