September 30, 2005
Anatomy of a Transmission: Oil Flow in the Pump-PR-Converter-Cooler Lube Circuits
Gregg Nader
The OE TCC regulated apply bore in GM 4T65-E units wears, causing TCC signal (PWM) oil and TCC regulated apply oil to leak. The leakage lowers the apply pressure, which causes the torque converter clutch to slip. Sonnax TCC regulated apply valve kit 84754-34K addresses TCC slip, code 741 and occasional ratio codes.
It is recommended to check separator plate orifices for contamination. Additionally, the TCC apply valve bore should be examined for wear with any TCC related concerns.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.
September 30, 2005
Gregg Nader
March 21, 2013