OverDrive for Automatic 95 SE

[ash1y1]

Can I drive with overdrive turned off? And if so, what are my restrictions as far as speed goes without having to kick into overdrive?

[boMex]

Yes you can drive with O/D off. You will be limited by how high the car can rev.

[UncleBen]

why would you wanna drive w/o OD on all the time? waste of gas, more ware and tear on the motor since its revving more, etc. everyonce and a while i'll drive w/ it off when i'm in town. oh and my favorite, when i'm slowin down from like 60 or sumthin, when i get to like 47 or close to that, i'll turn it off and the car will rev up back into 3rd. oh man, i love that. sounds just like a 5speed (which i'm gettin sometime)

[ash1y1]

Will this hurt the car in any way though?

[Aries]

so long as you're not toggling it back and forth constantly (like to feel it down-shift then up-shift then down-shift) it woln't to any harm.

If you are toggling it a LOT, then you could possibly burn out the relay and be stuck with it either on or off.

[rbboyl]

Playing around with the overdrive is the only redeeming factor of an automatic. OD basically turns off the final gear (4th), which means you can control how high you want 3rd to rev up to. You can probably reach 60 until you redline (never tried it so don't take my word for it).

I usually turn it off when I know I wont be driving over 40-45 miles per hour for a period of time, like in the city. I also use it to slow down sometimes so I dont have to use the brake as hard. If your going at about 25-50 mph with OD on, and you turn it off, you will feel the car slow down and drop in rpms.

OD on: Lower rpm, uses more gas?, better for the engine because it revs less

OD off: revs faster, no 4th gear, uses less gas but higher rpms? which means more wear and tear on the engine?

[Aries]

This is true.

But the speed difference is incorrect, my S-14 will rev to almost 80 before redline in 3rd.

It has a lot to do with tuning too...If you have an aftermarket ECU, you can have it re-programed for firmer shifts and a higher redline...

(Higher Redline on a stock motor with a chip may make the motor go boom)

[boMex]

Will this hurt the car in any way though?

No :sleep

[boMex]

OD on: Lower rpm, uses more gas?, better for the engine because it revs less

OD off: revs faster, no 4th gear, uses less gas but higher rpms? which means more wear and tear on the engine?

O/D on uses less gas, O/D off uses more. General rule of thumb: Higher revs use more fuel. So many people talk about the "wear and tear" that reving can cause to the engine. Too bad it's bs. A properly warmed up engine is actually quite lubricated and generates little damaging friction. The most "damage" done to your car is when your starting it. The oil is all down in the pan and so the pistons are sliding on dry cylinders. So long as you don't spend your time bouncing off the rev limiter your engine should last about the same amount of time regardless of whether you drive at 3500rpm or 6500rpm. :sleep

[UncleBen]

i love cruisin at like 45 in town w/ my 240 revvin at like 2700. sounds so nice:)

[ash1y1]

I played around with the OD yesterday and I got up to 80 MPH and didn't get passed 4000 RPMs. I was afraid I would hurt the engine so I left off. I'm sure I could have taken it to 90 without redlining.

[biggie]

Ok, OD:

First I've had my car up to about 105mph before the car switched into OD----with it on and just flooring it.

One thing to keep in mind, if you are in town(speed limit 35 or so and lots of red lights) you may want to keep it off. Stopping and slowing down so much will cause the OD to change gears too many times. This is one of the main reasons for automatics having OD problems.

[ash1y1]

Seriously? I thought overdrive on cars newer that 1990 was meant to be driven while "on" all the time. Hmm, I guess you learn something new every day. Thanks for the info guys.

[rbboyl]

Ok, OD:

First I've had my car up to about 105mph before the car switched into OD----with it on and just flooring it.

One thing to keep in mind, if you are in town(speed limit 35 or so and lots of red lights) you may want to keep it off. Stopping and slowing down so much will cause the OD to change gears too many times. This is one of the main reasons for automatics having OD problems.

Ok, yeah, thats what I've been told. Driving at lower speeds constantly with the OD on puts more wear on the transmission.

[UncleBen]

thats what i thought. my parents think i'm hurting the car by driving w/ it off....i'm just like yea, ok

[mars240]

**** i always drove with OD on nevrr really played with so i dunno but one day i tried it out and i noticed that its different when its of!! so u guys are sayin that its better to drive with OD off in the city ??? and then on the high way turn it on??

[boMex]

so u guys are sayin that its better to drive with OD off in the city ??? and then on the high way turn it on??

Yes, you silly newb

[dcmetro240]

Get a 5 spd, or 6 spd for that matter. But for most 5 spds, 5th is considered overdrive, so by you not letting the car change gears on it's own, your basically driving like it's a 5spd. No harm to the car at all.

[ash1y1]

Thank you guys for your replies. I have learned so much in these forums.

[UncleBen]

Thank you guys for your replies. I have learned so much in these forums.

:Werd :ylsuper

[zman]

My daughter's 1989 240SX has a similar overdrive problem. The OD light started flashing, then returned to normal. But the car will not go into overdrive now. Any ideas. A Nissan service guy tells me there is no relay.