Overdrive - On or Off?


I have a 2000 Toyota Echo with an automatic transmission. My father told me to just leave the overdrive on all the time. But today I was told leaving it on when I am under a certain speed will drastically reduce the life of my transmission. After looking online I am even more confused. What should I do? Leave it on or keep it off? And if I do keep it off, when and how should I use it?


Leave the overdrive ‘on’ for most driving. If you are not getting up to highway speed, the shift to overdrive will cause minimal wear. At highway speeds keep the overdrive ‘on’ unless you are in the mountains or pulling a heavy load. Lock overdrive out any time you need the engine to control decelleration or traction. That should cover most driving enviornments.


Researcher is right and I like to do things my way sometimes. If I’m in a 25 MPH zone I sometimes take the Yaris and the Echo out of OD. On a level road I will leave it in OD and not even think about it, but on these ups and downs I have good control of my speed, which is good because the police are all over this one road.


Whoever told you the OD would hurt your transmission is incorrect. Toyota would not design an automatic that would self-destruct.

Leave the OD on, as your father said. The transmission knows when to engage the OD, and when it is not necessary. You don’t need to worry about it.

OD reduces engine wear and increases fuel mileage. Why would you want to turn it off?


It does not matter whether the car is in OD or not. However, as pointed out by other posters, on long upgrades and mountains, a car like yours should be out of OD to have more power available for the uphill stretches. The same is true for trailer towing. In city traffic where you keep going from slow to near highway speed, and back, the car will keep shifting back & forth, so best to stay out of OD. Whatever you choose to do, it won’t affect the warranty.


I agree.

And, for a totally unbiased, authoritative explanation of what to do, when to do it, and why you should do it…read the section of your Owner’s Manual that deals with the transmission. I honestly don’t understand why so few people bother to refer to this great resource that is sitting in their glove compartment.


An automotive authority recently called the Owner’s Manual the “Most Unread Best Seller” in the world. It is indeed puzzling why so many people just don’t bother to read it. If you buy a used car and the manual is missing, the dealer should be able to get you one. If the seller is not a dealer, you can get a standard Haynes or other maintenance & repair guide which has a section on the care and feeding of your car. For about $15-20 many questions are answered.


So a Yaris is in overdrive by 25MPH? That doesn’t sound right.


Leave it in overdrive and don’t worry about it. When GM started using 4 speed automatics over 20 years ago, the torque converter lock up was set at a low speed (~ 30 to 35 mph) for best mpg. In city driving the torque converter would constantly lock and unlock putting excess wear and tear on the trans. This is how my mechanic explained it to me for my 86 Camaro. With the automatics I drive these days, the torque converter lock up engages at a more realistic 40 to 50 mph.

Ed B.


If you feel the transmission shifting in and out of overdrive constantly, which can happen in urban driving conditions when speeds are between 30 and 40 mph, then lock it out! That’s what the lock-out button is for! This WILL save a lot of wear and tear on the transmission. Just don’t forget to enable the overdrive when you can maintain 45mph or more…

Every time a transmission shifts, there is a little wear to the bands and clutches…


It isn’t too right, but if I let it go on a slight downhill, it will shift up and then I have to use the brakes. By keeping it in 3, I don’t have to work so hard to keep an even speed. Guaranteed not to if you keep it in 3.