IMPORTANCE OF PROPER FLUID LEVEL
It is important that the proper
fl
uid level be maintained at all times because the
transmission
fl
uid cools, lubricates, and transmits hydraulic power. If the
fl
uid
level is too low, the converter and clutches do not receive an adequate supply of
fl
uid. If
fl
uid level is too high, the
fl
uid can aerate. Aerated
fl
uid can cause the
transmission to shift erratically or overheat.
Motorhome Series transmissions have an oil level sensor (OLS) that allows the
operator to obtain an indication of
fl
uid level from the shift selector. However, no
oil level sensor diagnostics take place unless the OLS is “autodetected” by Allison
4
th
Generation Controls or WTEC III Controls.
Frequently check for the presence of oil level diagnostics if the transmission is
known to contain an OLS. If an OLS is not detected during a
fi
xed number of
engine starts, the WTEC III or Allison 4
th
Generation Controls system concludes
that no OLS is present. If an OLS is known to be present, but has not been
detected, then troubleshooting of the OLS circuit is required. After the OLS circuit
is repaired, reset “autodetect” or manually select the OLS function using Allison
DOC™ For PC–Service Tool. For detailed troubleshooting procedures refer to the
Troubleshooting Manual. Refer to the SERVICE LITERATURE section for
speci
fi
c publication numbers.
NOTE:
To correctly check the transmission
fl
uid level using the
dipstick, the transmission
fl
uid must be at operating temperature.
The oil level sensor method of checking the
fl
uid level compensates for
transmission
fl
uid temperature between 60°C–104°C (140°F–220°F).
Any temperature below 60°C (140°F) or above 104°C (220°F) will
result in an
Invalid for Display
condition.
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