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Shift Patterns




Shift Patterns


Upshifts

Upshifting is controlled by the PCM. The PCM receives inputs from various engine or vehicle sensors and driver demands to control shift scheduling, shift feel and Torque Converter Clutch (TCC) operation.

The PCM has an adaptive learn strategy to electronically control the transaxle which will automatically adjust the shift feel through the life of the vehicle. The first few hundred miles of operation of the transaxle may have abrupt shifting. This is a normal operation. To reset the adaptive shift pressure strategy, use the scan tool to clear the transmission keep alive memory tables.


Downshifts

Under certain conditions, the transaxle will downshift automatically to a lower gear range (without moving the selector lever). There are 3 categories of automatic downshifts: coastdown, torque demand and forced or kickdown shifts.


Coastdown

The coastdown downshift occurs when the vehicle is coasting down to a stop.


Torque Demand

The torque demand downshift occurs (automatically) during part throttle acceleration when the demand for torque is greater than the engine can provide at that gear ratio. If applied, the transmission will disengage the TCC to provide added acceleration.


Kickdown

For maximum acceleration, the driver can force a downshift by pressing the accelerator pedal to the floor. A forced downshift into a lower gear is possible below calibrated speeds. Specifications for downshift speeds are subject to variations due to tire size, engine and transaxle calibration requirements.