TCC Valve 4T65E
- PTFE Seals (2) 1 extra
With PTFE seal
Continuous oscillation of the converter apply valve in the cast-aluminum bore causes bore wear, particularly at the TCC signal valve spool closest to the solenoid. Wear in this area allows TCC signal oil to leak, which inhibits the valve from stroking to the lockup position. Due to the valve body casting design and oil flow, this valve is also subject to extreme side loading, which increases the wear rate. Early OE versions of this valve were made from non-anodized aluminum, and show significant wear marks. The TCC regulated apply valve should also be checked for wear. The Sonnax kit includes an O-ring to replace the OE O-ring on the TCC regulated end plug after inspection.
Falls out of lockup when hot
High TCC slip RPM
Continuous oscillation of the converter apply valve in the cast-aluminum bore causes bore wear that prevents the valve from stroking to the lock-up position.
The Sonnax kit provides a positive seal to ensure proper valve stroke, and more valve support to prevent side loading that leads to wear.
GM General Motors