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Hey guys i have been hearing some mixed opinions lately about the overdrive switch in my car and others.

I have heard that its good to leave overdrive on at all times and i have also heard its good leave overdrive off until you hit around 70km/h.

I have heard having it on all the time is good for fuel economy too although its not healthy for the gearbox?

Is there a definitive answer or is it just one of those "what you prefer" situations..

Thanks.

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Personally i never use 6th gear unless im on the freeway; 5th is the highest ill go on a highway.

Overdrive is great when you can keep a nice a smooth speed of over 60kph without having to slow down; etc comming home from work in traffic.

keep it off when you wanna weave through light traffic; feels great and much more responsive.

on the great ocean road; you would not turn on the overdrive.

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Personally i never use 6th gear unless im on the freeway; 5th is the highest ill go on a highway.

Overdrive is great when you can keep a nice a smooth speed of over 60kph without having to slow down; etc comming home from work in traffic.

keep it off when you wanna weave through light traffic; feels great and much more responsive.

on the great ocean road; you would not turn on the overdrive.

Yer i can see where your coming from, but in my situation, which is not relatively hard driving around the local streets would it be best to have it on or off?

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Definitely off mate and leave the power button off too; just normal mode.

going round residential roads and looking out for parked cars and street signs you wouldnt want it to jump into 4th gear when the 50km zone suddently has a hill or incline.

if you were in 4th you would have to put the foot down and you may be unlucky enough to hit the kickdown into 2nd; which is quite violent on the engine and gearbox.

I blew rocker arms off my sr20 s15 auto cos it drops down very quickly and the rev's shoot up

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Ah yer i have noticed that, put your foot down and then it just downshifts and revs sky rocket up.

Well thanks for your advice man, i will turn it off tomorrow and see how we go :D

Leave it on all the time. Save petrol, engine wear. Now that you know there is a kickdown switch you won't be surprised by what happens when you floor the pedal. You can develop a smooth driving style by managing the accelerator pedal to keep it in the highest possible gear and with practice you can make it go into 3rd or 2nd at will. The only time i would turn it off is if you are going down a steep hill while towing or if you are giving it hell through a winding stretch and you want to hold it in 3rd.

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Leave it on all the time. Save petrol, engine wear. Now that you know there is a kickdown switch you won't be surprised by what happens when you floor the pedal. You can develop a smooth driving style by managing the accelerator pedal to keep it in the highest possible gear and with practice you can make it go into 3rd or 2nd at will. The only time i would turn it off is if you are going down a steep hill while towing or if you are giving it hell through a winding stretch and you want to hold it in 3rd.

Just to clarify (looking at your other post there sems to be room for misunderstanding) when i say leave it on i mean normally leave the overdrive in operation i.e. do not use the overdrive off switch except as above.

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ok back to confusion haha!

overdrive is off when the light on the dash says overdrive off

overdrive is on when the light on the dash is not displayed

So basically for local driving it is best to have overdrive on which means the button should be pushed in leaving no light on the dash!

Correct or..

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ok back to confusion haha!

overdrive is off when the light on the dash says overdrive off

overdrive is on when the light on the dash is not displayed

So basically for local driving it is best to have overdrive on which means the button should be pushed in leaving no light on the dash!

Correct or..

correct.. thats what i would normally do. i normally just leave it on which means no lights on dash, except up hill and towing

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id love to see a comparison. between a full tank off petrol when the overdrive was not used and a full tank of petrol when the overdrive was left on. similar driving on both.

I have a feeling there may be a few suprises.

I would not sue overdrive unless I was going to stay at a constant speed above 80kmh for awhile

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Leave overdrive enabled (no light on the dash), let the computer do the work of selecting gears, learn to modulate the throttle pedal so you get good economy and make it kick down whenever you wish.

As stated above only time I'd turn it off is for engine braking/caning through twisties.

Overdrive = 4th gear/top gear

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while we are on the topic, what about manually down-gearing?

As in its in drive, slowing down for a corner and push it into 2nd at around 50ks...

Is this practise ok for auto-trannies?

I usually drive with the over-drive off during normal <70km/hr driving. If i get on the freeway/highway then i engage overdrive (or 4th gear). In a manual you dont go into 5th when doing 50km/hr do you? How would putting overdrive on (or not turning it off) cause less engine wear?

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