Allison Transmission Maintenance; Manual Fluid Level Check; Cold Check - PREVOST H3-41 Maintenance Manual

If the I-Shift transmission system is to be used,
the vehicle must have an electronic engine
control unit as well as CAN communication.
Since the clutch is automated (clutch pedal no
longer fitted), the driver no longer has to activate
the clutch.
FIGURE 3: VOLVO I-SHIFT TRANSMISSION
The transmitted torque (both engine and
braking) will be interrupted during gear shifting,
in both driving and coasting conditions. There is
no clutch pedal and the gear shifting is controlled
by the transmission or the driver through the
pushbutton shift selector.
When in fully automatic mode, gears are
selected and shifts made by the electronic
control unit. The driver can still intervene if he
wishes to. All system functions required are
shown on the display, e.g. neutral, gear change,
clutch overload and diagnosis information.
3. ALLISON TRANSMISSION
MAINTENANCE
3.1

MANUAL FLUID LEVEL CHECK

Take note that an oil level sensor (OLS) is
standard in your transmission. With the OLS and
Allison 5th generation shift selector, you can get
a more accurate electronic fluid level check than
with a dipstick.
To gain access to the dipstick, open the engine
compartment rear door; dipstick is located on the
radiator side of the engine (Figure 4).
Clean all dirt from around the end of the oil filler
tube before removing the dipstick. Dirt or foreign
matter must not be permitted to enter the oil
SECTION 07: TRANSMISSION
system since it will cause valves to stick, undue
wear of transmission
passages. Check
procedures in Cold Check and Hot Check. Record
any abnormal level on your "Maintenance
Records".
WARNING
When checking the oil level, be sure that the
parking brake and/or emergency brakes are set
and properly engaged, and the wheels are
chocked. Unexpected and possible sudden
vehicle movement
precautions are not taken.
o Special care must be taken not to touch the
engine coolant tubing and/or exhaust pipe,
since this could cause severe burns.
o Do not wear loose clothing and, stay away
from rotating
personal injury could occur.
FIGURE 4: OIL LEVEL DIPSTICK (ALLISON)
Always check the oil level reading at least twice
when the engine is running. Consistency is
important in maintaining the accuracy of the
reading. If inconsistent readings persist, check the
transmission breather to ensure it is clean and
free of debris.

3.1.1 Cold Check

The purpose of the Cold Check is to determine if
the transmission has enough fluid to be operated
safely until a Hot Check can be made.
CAUTION
PA1621 Maintenance Manual All Series | January 2017
parts, and clogged
the oil level using
may occur if these
parts during procedure;
7
the