How do I use overdrive?


I just got an 05 Pontiac Vibe, 17000 miles, automatic. It has an overdrive button and I don’t know what to use it for or what it does. The manual doesn’t tell me. Please help.

By the way, my last name is Jeep and I just retired my Jeep Grand Cherokee and am feeling a bit of an identity crisis.


The OD button will disable the overdrive when pressed. Pressing it again will turn the OD back on. A light on the instrument panel will tell you when it’s off.

Under normal conditions you want the overdrive to be ENGAGED and functioning, so leave the button alone.

If you are descending a long, steep hill, or towing, you may want to consider turning the OD off, but otherwise leave it on.

Overdrive reduces engine wear and increases fuel mileage, which are two good reasons to keep it on.


Ah ha! That may explain while my milage was 26 mpg on the last fill up and 33 on the two previous fill ups.
Thank you.


Aha, indeed! If you turned off the OD that would CERTAINLY explain the reduction in fuel mileage.

Your car has an Automatic Overdrive (AOD) transmission, meaning the transmission knows when to shift into overdrive and when to shift out of overdrive, and will do so as required.

Let the transmission do its job. Don’t try to manually ‘use’ the overdrive.