so for a while now i have been wondering what over drive does on out cars. unlike most cars i have drove, it is always on in this car. i mean the light says "O/D Off" where as most cars alert you when you have it on
i have been told A LOT OF THINGS about it, but i am really not sure what to believe

just to clarify, i am not wondering what is "better" for the car, i am just wondering what it does


thanks, any info would really be nice

 

Over drive is 5th gear basically on the mustangs. Its the only gear where the engine's RPMs are lower than the transmission's RPMs, where as in 1-3 the engine spins faster than the tranny and in 4th the RPMs are matched, at least thats how it works to my understanding, Im sure there are some pros here who can correct me if Im wrong.

So basically the overdrive gear is for fuel economy, but it has very low power, so youw ant to turn it off if youre going uphill or towing something so you stay in the 4 underdrive gears with more power.

 

Overdrive by nature is a fuel saver, intended to utilize the highest gear when cruising. Some cars use a torque converter lock-up as an OD.

My Mitsu Galant had a bright yellow light in the center of the cluster that said OD OFF. It's better to tell you when it's off than when it's on 'cos in the Galants case, OD was 4th, so the OD off gave you a 3spd. I would assume it is this way in the Stang, but I know someone else knows for sure.

EDIT: Red beat me to it. I guess I type to slow.

 

so let's say i am driving along with overdrive on, and i want to "downshift" to 4th, can i just turn overdrive off?

 

That should work but not instantaniously, I havent driven auto in a while, also if youre cruising along on the highway in 5th gear and you floor the gas the computer recognizes that your trying to pass and will automatically downshift for you, hence the little kick you feel and then the engine gets really loud.

 

Yes.

 

The overdrive really helps when you change the rear gears . Now I do not have to turn it off at 55 mph for a quicker acceleration.

 

I couldn't find an answer on this either so I use the following rules: I leave it on unless:

I'm in bad stop & go traffic
I just want to get more performance out of her such as getting through traffic at a light or on the highway
I'm going up a big hill
snow

Basically, I leave it on unless I might have to push the car a little harder. (I'm still careful with it anyway) The manual says to turn it off in city traffic, when you're towing something (lol), or in hilly terrain.

 

Weather it's on or off doesn't matter. Slap it WOT and your Horse will get the idea

 

I turn it off when at the track and when im driving and want higher rpms.