What is overdrive and what does it do?

Question

My 2003 Carolla has a little button that says overdrive. When i push it a light on the dashboard comes on that says o/d off. What is overdrive and what is it for? Should I leave it on or off? Thanks any help would be appreciated and I'll vote best answer :)

Answer 1

Overdrive is the top gear in your transmission.

it provides high speed, but very low power.

If you are accelerating, climbing, or towing overdrive is useless.

If you are driving at pretty constant speed (such as the highway) then using overdrive will save you alot of gas and wear on your engine.

If you are going up or down a hill, towing, or in stop and go traffic, you should leave overdrive off.

Answer 2

use it when driving in higher speeds such as around 60 or so for gas saving...its like a 5th gear

Answer 3

Overdrive is a setting on your transmission. When your car changes gears, it begins with a small gear connecting to a big gear.(I like to visualize it like a 10 speed bike) As it changes, that big gear gets smaller and smaller, so you tires spin faster without making you engine run at a million revolutions per minute(RPM). Overdrive actually takes that big gear, and makes it smaller than the first, so your car is outputting more revolutions than it gives your transmission.

As far as on or off, if you travel on the highway often, keep it on. It will save you gasoline, because your engine will be able to travel faster at a lower RPM.

If you don't travel on the highway, it doesn't matter either way, because it won't get to that gear anyway. (only kicks in after the highest gear, usually the 4th or 5th, or around 60-70MPH.

Hope this helps.

Answer 4

An overdrive is a device which was commonly used on rear-wheel drive automobiles to allow the choice of an extra-high overall gear ratio for high speed cruising, thus saving fuel, at the cost of less torque.

So it is suggested you leave it on.