Why Overdrive Is Used?

Usage. Generally speaking, overdrive is the highest gear in the transmission. Overdrive allows the engine to operate at a lower RPM for a given road speed. This allows the vehicle to achieve better fuel efficiency, and often quieter operation on the highway.

Is it better to drive with overdrive on or off?

Overdrive improves fuel economy, and makes for less wear and tear on the vehicle when you are driving at highway speeds. Having the overdrive off is fine if you are driving in hilly areas, but if you are on the highway, it is best to have it on because you will get better gas mileage.

When should I use overdrive mode?

You engage the overdrive gear to get better gas mileage when traveling at high speeds. It enables the engine to turn at lower RPMs while maintaining the same wheel speed; your engine doesn't need to do as much work to maintain the same wheel speed.