F 250 2WD Super Duty V8-5.4L (2008)
Torque Converter: Testing and Inspection
Torque Converter Diagnosis
Torque Converter Diagnosis
Prior to torque converter replacement, all diagnostic procedures must be followed. This is to prevent the unnecessary installation of new or
remanufactured torque converters. Only after a complete diagnostic evaluation can the decision be made to install new or remanufactured torque
converters.
NOTE: If equipped, turn the power take-off (PTO) unit off for correct test results.
During PTO operation, the on-board diagnostics will be disabled. However, the circuit checks made by the diagnostic system and the FMEM will
continue. The PTO must be turned off to do on-board diagnostics.
Begin with the normal diagnostic procedures as follows:
1. Preliminary Inspection.
2. Know and Understand the Customer's Concern.
3. Verify the Concern - Carry out the Torque Converter Clutch Operation Test.
4. Carry out Diagnostic Procedures.
^
Run on-board diagnostics. Refer to On-Board Diagnostics with Scan Tool.
-
Repair all non-transmission-related DTCs first.
-
Repair all transmission DTCs.
-
Rerun on-board diagnostics to verify repair.
^
Carry out Line Pressure Test. See: Transmission Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Line
Pressure Test
^
Carry out Stall Speed Test. See: Transmission Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Stall Speed
Test
^
Carry out Diagnostic Routines. See: Transmission Control Systems/Testing and Inspection/Symptom Related Diagnostic
Procedures/Engagement Concerns 201-209 See: Transmission Control Systems/Testing and Inspection/Symptom Related Diagnostic
Procedures/Shift Concerns 210-249 See: Transmission Control Systems/Testing and Inspection/Symptom Related Diagnostic
Procedures/Torque Converter Clutch Operation Concerns 250-253 See: Transmission Control Systems/Testing and Inspection/Symptom
Related Diagnostic Procedures/Other Concerns 254-267
-
Use the Diagnosis by Symptom Index to locate the appropriate routine that best describes the symptom(s). The routine will list all possible
components that may cause or contribute to the symptom. Check each component listed. Diagnose and repair as required, before repairing
the torque converter. See: Transmission Control Systems/Testing and Inspection/Symptom Related Diagnostic Procedures/Diagnosis By
Symptom
Torque Converter Operation Test
This test verifies that the torque converter clutch control system and the torque converter are operating correctly.
1. Carry out Quick Test, refer to On-Board Diagnostics with scan tool. Check for DTCs. Refer to the Diagnostic Trouble Code Chart. See:
Transmission Control Systems/Testing and Inspection/Diagnostic Trouble Code Descriptions
2. Connect a tachometer to the engine.
3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in (D) position.
4. After normal operating temperature is reached, maintain a constant vehicle speed of about 80 km/h (50 mph) and tap brake pedal with the left foot.
5. Engine rpm should increase when brake pedal is tapped and decrease about 5 seconds after pedal is released. If this does not occur, refer to
Diagnosis By Symptom - Torque Converter Clutch Operation Concerns. See: Transmission Control Systems/Testing and Inspection/Symptom
Related Diagnostic Procedures/Torque Converter Clutch Operation Concerns 250-253
