PRE-RELEASE
Transmission Adaptive Functions
| Transmission Adaptive Functions |
The 6T70/75 transmission utilizes a line pressure control system during upshifts to compensate for the normal wear of transmission components. As the apply components within the transmission wear or change over time, shift time (the time required to apply a clutch) increase or decreases. In order to compensate for these changes, the transmission control module (TCM) adjusts the pressure commands to the various PC solenoids, to maintain the originally calibrated shift timing. The automatic adaptation process is called "adaptive learning" and is used to ensure a uniform gearshifting feel and to increase the transmission's durability. TCM controls the transmission's input speed sensor (ISS) and output speed sensor (OSS) during shifting to determine if it takes place too fast (harsh) or too slow (soft) and adapts the corresponding signal from the pressure control solenoid to maintain the set gearshifting feel.
The purpose of the adapt function is to automatically compensate the shift quality for the various vehicle shift control systems. The adapt function is a continuous process that will help to maintain optimal shift quality throughout the life of the vehicle.
