50 Dana Incorporated TSM-0238 - 6000 Transmission Service Manual
TROUBLESHOOTING
The following information is presented as an aid to isolate and determine the specific problem areas in a transmission that is
not functioning correctly.
When troubleshooting a “transmission” problem, it should be kept in mind that the transmission is only the central unit of a
group of related powertrain components. Proper operation of the transmission depends on the condition and correct functio-
ning of the other components of the group. Therefore, to properly diagnose a suspected problem in the transmission, it is ne-
cessary to consider the transmission fluid, charging pump, torque converter, transmission assembly, oil cooler, filter,
connecting lines, and controls, including the engine, as a complete system.
By analysing the principles of operation together with the information in this section, it should be possible to identify and correct
any malfunction which may occur in the system.
TRANSMISSION PROBLEMS
6000 Transmission troubles fall into three general categories:
1 - Mechanical problems.
2 - Hydraulic problems.
3 - Electrical problems.
In addition to the mechanical and electrical components, all of which must be in the proper condition and functioning correctly,
the correct functioning of the hydraulic circuit is most important. Transmission fluid is the “life blood” of the transmission. It
must be supplied in an adequate quantity and delivered to the system at the correct pressures to ensure converter operation,
to engage and hold the clutches from slipping, and to cool and lubricate the working components.
TROUBLESHOOTING PROCEDURES
INPUT SHAFT AND DIRECTIONAL CLUTCH PROBLEMS
Stall Test
A stall test to identify transmission, converter, or engine problems.
Use following procedure:
1 - Put the vehicle at standstill, apply the parking brake, and block the wheels.
2 - Select “Manual Mode” Drive.
3 - Put the directional control lever in FORWARD (or REVERSE, as applicable).
4 - Select the highest speed.
5 - With the engine running, slowly increase engine speed to approximately one-half throttle and hold until transmission (con-
verter outlet) oil temperature reaches the operating range. Always check that vehicle is not moving while increasing engine
RPM.
TRANSMISSION PRESSURE CHECKS
Transmission problems can be isolated by the use of pressure tests. When the stall test indicates slipping clutches, then mea-
sure clutch pack pressure to determine if the slippage is due to low pressure or clutch plate friction material failure.
In addition, converter charging pressure and transmission lubrication pressure can also be measured.
MECHANICAL AND ELECTRICAL CHECKS
Prior to checking any part of the system for hydraulic function (pressure testing), the following mechanical and electrical checks
should be made:
• Check the parking brake and inching pedal for correct adjustment.
• Be sure all lever linkage is properly connected and adjusted in each segment and at all connecting points.
• The controls are actuated electrically. Check the wiring and electrical components.
• Be sure that all components of the cooling system are in good condition and operating correctly. The radiator must be clean
to maintain the proper cooling and operating temperatures for the engine and transmission. Air clean the radiator, if neces-
sary.
• The engine must be operating correctly. Be sure that it is correctly tuned and adjusted to the correct idle and maximum no-
load governed speed specifications.
Do not operate the converter at stall condition longer than 30 seconds at one time, shift to neutral for 15 seconds and repeat
the procedure until desired temperature is reached. Excessive temperature 120°C [250°F] maximum will cause damage to
transmission clutches, fluid, converter, and seals.
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