Catching torque converter failure early saves a transmission. Here are the 7 warning signs and what to do.
1. Shudder at TCC engagement
- Felt at 40-60 mph cruise
- Lockup clutch worn / contaminated
- Read our 6L80 shudder fix
2. Slip at all speeds
- Engine revs without acceleration
- Converter internal failure (clutch / stator)
- Read our transmission shudder vs slip
3. Whine that changes with engine RPM
- Converter bearing failure
- Pump damage from converter wobble
- Read our transmission noise diagnosis
4. Hard / no shifts
- Converter not coupling properly
- Stator problem
- Trans hydraulic damage downstream
5. Stalling at stops
- TCC stuck on
- Read our 4L60E P0742 TCC stuck on
6. Slow acceleration
- Stall speed off (low)
- Stator vanes damaged
- Read our torque converter stall speed
7. Trans fluid burnt or contaminated
- Converter clutch friction material in fluid
- Brown/black tint instead of red
- Read our burnt transmission fluid
Diagnosis
- Stall test (verify spec stall RPM)
- Pressure test cooler flow
- Pan inspection for debris
- Read our transmission pan inspection
Repair
- Replace converter always when symptoms present
- Cost: $200-$700 part
- Plus install labor (combined with rebuild usually)
- Pair with new pump bushing/seal
- Read our 4L80E pump bushing
Prevention
- Aux cooler for tow
- Service fluid intervals
- Right stall for your engine
- Read our transmission cooler installation
Don't ignore
- Bad converter = bad trans
- Read our transmission warning signs
Need torque converter or trans parts? Shop our catalog. Standard, HD, high-stall, billet converters. Free shipping over $70.
Related: