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4R70W/4R75W



4R70W/4R75W TRANSMISSION

Output Shaft Speed (OSS) Sensor

The output shaft speed (OSS) sensor is a magnetic pickup, located at the output shaft ring gear, that sends a signal to the powertrain control module (PCM) to indicate transmission output shaft speed. The OSS sensor is used for torque converter (TCC) control, shift scheduling and to determine electronic pressure control (EPC).


Turbine Shaft Speed (TSS) Sensor

The turbine shaft speed (TSS) sensor is a magnetic pickup, that sends a signal to the powertrain control module to indicate transmission turbine shaft speed. The TSS is mounted externally on the case. The PCM uses the TSS signal to help determine appropriate operating pressure and torque converter clutch (TCC) operation.