Shift Patterns
Upshifts
Transmission upshifting is controlled by the powertrain control module (PCM) . The PCM receives inputs from engine sensors, transmission sensors, vehicle sensors, and driver demands to control upshifting.
Downshifts
Under certain conditions, the transmission will downshift automatically to a lower gear range. There are three types of automatic downshifts:
- Coastdown.
- Torque demand.
- Kickdown.
Coastdown
Coastdown downshifts occur when a vehicle is decelerating or coasting down to a stop. The PCM uses various inputs to control automatic downshift scheduling.
Torque Demand
The torque demand downshift occurs during part throttle acceleration when the demand for torque is greater than the engine can provide at that gear ratio. The PCM controls the downshifts to achieve driver demands.
Kickdown
The driver can force a downshift by fully pressing the accelerator pedal to the floor.
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