Recommended shifting speeds
Subaru Impreza / Subaru Impreza Owners Manual / Starting and operating / Manual transmission – 5 speeds (except STI) / Shifting speeds / Recommended shifting speeds
The best compromise between fuel economy and vehicle performance during normal driving is ensured by shifting up at the speeds listed in the following table.

See also:
Rocking the vehicle
If you must rock the vehicle to free it from snow, sand, or mud, depress the accelerator pedal slightly and move the shift lever/select lever back and forth between “1”/“D” and “R” repeatedly. Do not ...
Models without HID headlights
NOTE
This vehicle does not contain mercury
devices or parts. ...
Behavior with key lock-in prevention function operational
With the driver’s door open, the doors are automatically kept unlocked even if
the front side of the power door locking switch is pressed. ...
