Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Drive vs. Overdrive

I was wondering if a person should use drive or overdrive when driving for every day on a mostly flat terrain? My husband says to use overdrive, but I thought that was mostly for bad weather or steep inclines.

overdrive is the preferred method as you describe

I assume automatic? My understanding is that most transmissions will switch in and out of overdrive as needed. You can easily check for that yourself. Just turn on overdrive and watch engine RPMs (or listen). Does the engine speed up when you get to a hill? that is overdrive switching off.

Actually you have it backwards, overdrive is for level ground and speeds above about 50mph. If you are driving on a lot of hills, leave it off.

Look at overdrive as an extra gear, higher than the others.

Modern overdrive is nothing more than a high gear that allows you to save fuel and decrease wear on the engine. You should use the overdrive unless you are towing or you notice the transmission shifting more than normal between gears.

As Mr. Russell stated, you have it exactly opposite to reality, and for the type of driving that you mentioned (mostly flat terrain), the overdrive position on your shift lever is the one that you should be using. If you observe your tachometer when the car is in overdrive, you will see that it registers lower RPMs at highway speed than when it is not in overdrive. The lower RPMs translate into better fuel economy and longer engine life.

But, why should you take the word of anyone in this forum?
By simply opening your glove compartment, taking out the Owner’s Manual*, and reading that book, you can get the official word from the people who designed and manufactured your car.

*Owner’s Manual–The least-read best seller in the world. Those who do not read it inevitably live to regret that omission.

Think of overdrive as your cruising gear on the highway. The manufacturers have it programmed well, so you should really just leave your transmission alone and don’t lock out overdrive. Jeremy provided some useful information about when to lock it out.

It is probably best to keep the overdrive turned on except when in terrain where the transmission shifts between gears, such as in the mountains. It is best left off also when decending.