Automatic transmission speeds are usually switched under the following conditions:
Shifting up (to a higher gear):
* A certain vehicle speed has been reached
*A certain engine speed has been reached (to prevent excessive fuel consumption)
* Throttle opening is partial or moderate (indicating normal driving)
Shifting down (to a lower gear):
* Certain vehicle speed is reduced
* Engine speed has dropped below a certain threshold (to prevent speed failure)
* Full or wide throttle opening (indicating acceleration or hill climbing)
* Quick throttle release (for example, when braking the engine)
The exact gear shift points vary depending on:
*Car makes and models
* Automatic transmission software
* Driving modes (e.g. Economy, Sport, Manual shift)
* Engine load (vehicle weight, road slope)
For example:
*For a typical 6-speed automatic transmission, upshifting can occur at the following speeds:
* 2nd to 3rd: 15-20 km/h
* 3rd to 4th: 40-50 km/h
* 4th to 5th: 60-70 km/h
* 5th to 6th: 80-90 km/h
* Downshifting may occur when the vehicle speed drops 5-10 km/h below the upshift speed.