Torque Converter Diagnosis Procedure
The Torque Converter Clutch (TCC) is applied by fluid pressure, which is controlled by the TCC clutch control solenoid valve. This solenoid valve is located inside the automatic transmission assembly. The solenoid valve is controlled by the TCM.
Torque Converter Stator
The torque converter stator roller clutch can have two different malfunctions.
- The stator assembly freewheels in both directions.
- The stator assembly remains locked up at all times.
Torque Converter Clutch Shudder
The key to diagnosing Torque Converter Clutch (TCC) shudder is to note when it happens and under what conditions.
TCC shudder which is caused by the transmission should only occur during the apply or the release of the converter clutch. Shudder should never occur after the TCC plate is fully applied.
If the shudder occurs while the TCC is applying, the condition can be within the transmission or the torque converter. Something is causing one of the following conditions to occur
- Something is not allowing the clutch to become fully engaged.
- Something is not allowing the clutch to release.
- The clutch is releasing and applying at the same time.
One of the following conditions may be causing the shudder to occur
- Leaking turbine shaft seals
- A restricted release orifice
- A distorted clutch or housing surface due to long converter bolts
- Defective friction material on the TCC plate
Torque Converter Evaluation and Diagnosis
Replace the torque converter if any of the following conditions exist
- External leaks appear in the hub weld area.
- The converter hub is scored or damaged.
- The converter pilot is broken, damaged, or fits poorly into the crankshaft.
- You discover steel particles after flushing the cooler and the cooler lines.
- The pump is damaged, or you discover steel particles in the converter.
- The vehicle has TCC shudder and/or no TCC apply. Replace the torque converter only after all hydraulic and electrical diagnoses have been made. The converter clutch material may be glazed.
- The converter has an imbalance which cannot be corrected. Refer to «Flexplate/Torque Converter Vibration Test»(ref-188833-S15746351542005090200000) .
- The converter is contaminated with engine coolant which contains antifreeze.
- An internal failure occurs in the stator roller clutch.
- You notice excessive end play.
- Overheating produces heavy debris in the clutch.
- You discover steel particles or clutch lining material in the fluid filter or on the magnet, when no internal parts in the unit are worn or damaged. This condition indicates that lining material came from the converter.
DO NOT REPLACE the torque converter if you discover any of the following symptoms
- The oil has an odor or the oil is discolored, even though metal or clutch facing particles are not present.
- The threads in one or more of the converter bolt holds are damaged. Correct the condition with a new thread inset.
- Transmission failure did not display evidence of damaged or worn internal parts, steel particles or clutch plate lining material in the unit and inside the fluid filter.
- The vehicle has been exposed to high mileage only. An exception may exist where the lining of the torque converter clutch dampener plate has seen excess wear by vehicles operated in heavy and/or constant traffic, such as taxi, delivery, or police use.
Indexing Torque Converter
To determine and correct a torque converter vibration, the following procedure may have to be performed several times to achieve the best possible torque converter to flywheel balance.
- Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-188813-S15240900572005090200000) in General Information.
- Rotate the torque converter one bolt position.
- Align the torque converter hub (1) in the engine crankshaft (2) and install the torque converter to flywheel bolts. Refer to «Transmission Replacement»(ref-188804-S03198339012005090200000) .
- Lower the vehicle.
- With the engine at idle speed and the transmission in PARK or NEUTRAL, observe the vibration. Refer to «Noise and Vibration Analysis»(ref-188833-S03245169322005090200000) .
- Repeat this procedure until you obtain the best possible balance.
- Install the transmission converter cover bolts and the cover. Refer to «Transmission Replacement»(ref-188804-S03198339012005090200000) .
No Torque Converter Clutch (TCC) Apply/TCC Slipping/Soft TCC Apply
| Checks | Action |
|---|---|
| Stator shaft assembly (81) | Inspect if the component contains debris or is damaged - causing restricted fluid flow and increased fluid temperature. Replace the transmission case assembly (50). Refer to Case Cover Assembly Removal . |
| Torque converter and housing seal assembly (2) | Inspect for looseness or damage. Replace the torque converter and housing seal assembly (2). Refer to Drive Axle Shaft Seal Replacement (FWD Right) or Drive Axle Shaft Seal Replacement (AWD Right) . |
| Line limit valve (310) and spring (309) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Control valve body (305) | Inspect for porosity, damage, or contamination with debris. Replace or flush the control valve body (305). Refer to Control Valve Body Replacement . |
| TCC control valve (308) and spring (307) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| TCC regulator valve (319) and apply valve spring (320) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
No Torque Converter Clutch (TCC) Apply/TCC Slipping/Soft TCC Apply
Torque Converter Clutch (TCC) Stuck On
| Checks | Action |
|---|---|
| Line limit valve (310) and spring (309) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Control valve body (305) | Inspect for porosity, damage, or contamination with debris. Replace or flush the control valve body (305). Refer to Control Valve Body Replacement . |
| TCC control valve (308) and spring (307) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| TCC regulator valve (319) and apply valve spring (320) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
Torque Converter Clutch (TCC) Stuck On
Harsh Torque Converter Clutch (TCC) Apply
| Checks | Action |
|---|---|
| TCC control valve (308) and spring (307) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| TCC regulator valve (319) and apply valve spring (320) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Line limit valve (310) and spring (309) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Actuator feed limit valve (312) and spring (311) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Primary limit valve (314) and spring (313) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
Harsh Torque Converter Clutch (TCC) Apply
Torque Converter Clutch (TCC) Slipping
| Checks | Action |
|---|---|
| Line limit valve (310) and spring (309) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Actuator feed limit valve (312) and spring (311) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| Primary limit valve (314) and spring (313) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| TCC control valve (308) and spring (307) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
| TCC regulator valve (319) and apply valve spring (320) | Inspect for wear, sticking, binding or damage. Refer to Control Valve Body Assembly Disassemble . |
Torque Converter Clutch (TCC) Slipping