How do you turn on OD?

Answer

On most cars the overdrive is on when you start the car and put it in gear. This is the D (drive) with a circle around it meaning "overdrive". Cars with a center console shifter the overdrive button is usually on the side of the gear shift.

You will know if the OD is off because a light on the dash will come on that says O/D off. If it is off there is usually a button on the gear shifter if you have a center console on down on the console next to the shifter.