General Information

The transmission that is used in this vehicle is the Hydra-Matic 4L30-E. The transmission is a four speed automatic with a torque converter clutch that provides a direct coupling to the engine when desired. The gear changes, the line pressure, and the torque converter clutch operation are controlled by an electronic control system. This system uses a separate Transmission Control Module (TCM). Certain specific signals are sent between the TCM and the ECM on the dedicated circuits for each signal. The TCM system also has self diagnostic capabilities.