Mack M359 - Preheating; Transmission Temperature

STARTING AND DRIVING
STARTING THE VEHICLE
NOTE
Failure to follow these procedures during
cold uid conditions, may cause the
CHECK TRANS light to illuminate and the
transmission to be restricted to N
(Neutral).
Preheating
CAUTION
Transmission malfunction or damage may
occur if you operate the transmission with
the uid temperature below the minimum
uid temperature specication limit.
CAUTION
The engine should never be operated for
more than 10 seconds at full throttle with
the transmission in range and the output
stalled. Prolonged operation of this type
will cause the transmission uid
temperature to become excessively high
and will cause severe overheat damage to
the transmission.
If ambient temperatures drop below the
specied minimum levels for the uid
type, preheat the transmission uid
before beginning transmission
operation.
Preheat the transmission uid using one
of the following methods:
• Use an auxiliary heat source such as
a sump heater.
• Operate the transmission in N
(Neutral) with the engine running at
idle for a minimum of 20 minutes
before attempting range operation.
Transmission Temperature
The Allison transmission uid is
minimum temperatures are:
• Fluid Type; TES 295, Minimum
Temperature: -35° C (-31° F).
• Fluid Type; TES 389, Minimum
Temperature: -25° C (-13 F).
The transmission is considered
overheated if the temperatures are:
• Sump uid; 121° C (250° F)
• Fluid to cooler; 149° C (300° F)
• Retarder out uid; 165° C (330° F)
Typical continuous sump temperature is
93° C (200° F).
If the engine temperature gauge
indicates a high temperature, the
transmission is probably overheated.
Stop the vehicle and check the cooling
system. If it appears to be functioning
properly, run the engine at 1200–1500
rpm with the transmission in N (Neutral).
This should reduce the transmission and
engine temperatures to normal operating
levels in 2 or 3 minutes.
If the transmission and engine
temperatures do not decrease, reduce
the engine rpm. If the engine
temperature indicates a high
temperature, an engine or radiator
problem is indicated. If high temperature
in either the engine or transmission
persists, stop the engine and have the
overheating condition investigated by
maintenance personnel.
NOTE
Some shift schedules may be inhibited as
a result of operating conditions, such as
engine or transmission uid temperature.
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X Publication_PC28