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When to switch overdrive off and on

I searched and read some posts from some months ago but am still a bit confused. I have an overdrive switch on my gearshift (auto) and wondering when is the appropriate time to turn it on. It has been off since I acquired the vehicle in October. An '09 Accent.



Thanks for any clarification you can provide.

Only time you need to turn over drive off is when you’re towing something. Since it’s an Accent, it can’t tow anything, so leave it on

You might consider turning it off when you go down a long hill and don’t want to be in overdrive. I’d leave it on all the time. You will use less gas if you leave it on.

Steep Hills or questionable road conditions, any time you need extra engine braking.

In all cars that I have driven, overdrive is “ON” unless you turn it “OFF”. I think it is a good idea to turn it “OFF” if you are off the highway and are in a lot of hills. This keeps it from shifting up going downhill and shifting down going uphill.

Check your manual, it should tell you, and make sure you know which position is on and which is off. I leave mine on 99% of the time, turn it off only when mild engine braking is needed. There’s no problem with leaving it on, it’s just another gear in the transmission.

I turn mine “off” until my average road speed is over 50 mph. This prevents MUCH useless shifting and wear & tear on the transmission and the torque converter lock-up. In most cars you can feel the transmission endlessly “hunt” between gears when driving between 40 & 50 with the overdrive “on”, its normal position. In some cars this is more noticeable than others…

If you want maximum gas mileage, and if you want to limit engine wear, you will leave the switch in the ON position almost all of the time. The only time to turn it off is if you are driving in hilly terrain.

However, as has already been suggested, this topic–as well as virtually everything else that you need to know regarding the safe and economical operation of your car–should be covered in your Owner’s Manual. It is not written in a technical manner, but rather, is written so that anyone–car oriented or not–can understand and benefit from the information. You REALLY need to begin to read your Owner’s Manual.

Generally, for engine braking and for in town driving where the shift point is around the speed limit you plan to abide by; In my opinion.

VDCdriver and texases, just so you know I am not some irresponsible schlub, I have actually read almost all of my owner’s manual (just the maintenance section left), but was still confused about the overdrive. I guess part of it is nerves, since I had to replace the transmission on my last car.

As someone mentioned earlier I was confused about when it’s on and off. It has been on all this time. With my old car I left it on all the time except when driving over the mountain when going to a friend’s house. That is what I will continue to do, per advice here. Thanks to you all.