Overdrive
 

12 times black Hey everyone,
when you have the overdrive one, does this effect gas milliage of the car in comparison to not having the overdrive on, and what exactly does the overdrive do?

Thanks
:shift:

From what I experinced overdrive lets the engine rev higher before changing gears. Since you rev higher before switching gears you will use more gas. From what I've been told people use overdrive when cornering at high speeds so the car doesn't shift into the lower gear providing for smoother cornering. Someone please correct me if i'm wrong.

That's what I thought it was for but then someone told me no it wasn't so I wanted to be sure, but that sounds about right to me.
thanks
:shift:

I use overdrive as a means to slow my car down in the winter without using the brake. It allows my car to use engine braking instead of locking up the tires. I simply let off the gas, hit overdrive button and rpms go up, but cars slows sing engine braking and then start pumping brakes. I know people who use it for uphill driving. Tranny shifts less when you turn overdrive off and is supposed to be easier on tranny. Same as for towing light trailers or a 5 adult in car party commute. Some people seem to think car pulls better when passing. Others use it to make there fart cans and intakes scream a little louder. :) Hope this helps!

OMG ! wow! let me educate you! Overdrive is your fourth gear on the ATX tranny. It is PURELY for gas mileage. It's geared lower(higher?) so the engine doesnt rev as high to acheive the same speed...does NOTHING for acceleration or top speed. In fact if you step on it hard, the tranny should downshift to take you out of overdrive and put you back in the powerband so you can accelerate faster. Turning the overdrive off just prevents you from shifting into fourth(overdrive). Please guys if you really don't know, don't answer.

Wow is right! macdaddyslomo is right, your transmission has 4 forward gears (1st, 2nd, 3rd, and 4th or "OD") and 1 reverse gear. Overdrive does exactly what it sounds like, it drives the output shaft of the transmission at a higher rate than the input shaft, meaning your motor turns less RPM's at the same MPH. In the lower gears, your motor turns more than the output shaft does, which multiplies the torque, provides easier acceleration, and helps keep your engine in its optimum power range.

Oh god. How did they not know that! Overdrive doesn't do much for the protege... at 30-35 mpg... its pretty taint as it is. My old 4 banger got 45 mpg.. believe me. Im feeling it. I drive 600 miles a weekend, thats alot of gas. Maybe Ill convert to vegetable oil.

So on an '02 ES, should I drive with OD on or off during normal city driving?

typically, the car will keep itself out of overdrive.. but if you're really worried about it.. keep it off.

Actually, our cars move into 4th gear at fairly low speeds. With electronically controlled trannies like we have, the computer makes gear selections based off speed and throttle position. If you're just barely on the gas around town, by the time you hit 30-40 MPH you'll probably be in 4th. But, if you're more aggressive with the go-pedal, it'll stay in lower gears to keep you in the powerband and provide better acceleration. For fuel economy, leave it in OD, but if you tend to drive aggressively all the time around town, turning it off will save a little wear on the tranny by it not having to hunt for gears quite as much.

Ok, I have a '03 LX Protege, and I drive with the overdrive off, for city driving and my cousin told me that when I do highway driving to turn the overdrive on. This is correct I understand right?
:shift:

That's correct! Otherwise, you'd be cruising at over 4,000RPM. Not good for fuel economy.

lol... I cruise at 4k anyway.. cause I'm typically doin 80..... hmmmmmm

fiveseven: I feel your pain. I drive about 250 miles a day as a bank courier in my '02. Even though I am paid per mile on top of the wages, the fluctuation in gas prices comes out of my pocket. My old 1996 1.5L got about 37-39 MPG, my 02 with the 2.0L gets about 31-32. It's times like this I almost miss the old torqueless wheezer. I said "almost." :)

On the highway, you definitely want the OD on, unless maybe you're on some really fun mountain roads! Around town you CAN turn it off, although you'll probably lose a little mileage. As I said, under light throttle conditions, by about 35 MPH you'll be in 4th gear already. Our car has enough low end torque to handle this high gearing, and is pretty good about downshifting when you really need it, so unless you just like putting more wear (albeit a small amount) on your motor, just leave it on.