Is my car faster with overdrive on or off?

Question

Ok so I drive an automatic 4 cylinder 2005 scion xb and I see it has an overdrive button, I know it has to deal some with gas mileage but I don't quite get it, will my car go faster with overdrive on or off? I want to go alot faster since this car has a slow acceleration. But also please explain to me what overdrive is and what purpose it serves as well.

Answer 1

On, until you start to go uphill.

Answer 2

Assuming it's a 4 speed auto, there will be absolutely no difference in acceleration at WOT (wide open throttle), at least until you hit the red line or computer-controlled shift point at the top of 3rd gear. Whether the car will go "faster" after that depends on how much power the car has. The top of 3rd at red line is probably close to 90 mph, with overdrive "engaged" the car might in theory reach 150 mph, but I doubt a Scion xB can pull the red line in 4th "overdrive". Air drag goes up as the square of velocity, and I think you'd be luck to see much more than 110 to 120 mph. Disengaging the overdrive probably also shuts off torque converter lockup, which means that the torque converter is going to be shearing the heck out of the tranny fluid, and generating a lot of heat. It's a quick way to ruin the drivetrain. It might feel and sound "faster", but it's just tearing up the car and you'd probably be getting about 8mpg driving like that. Leave it engaged, unless you are towing something or you have the thing loaded to the gills and you are in very hilly country at highway speeds. The owner's manual will tell you when it's useful to use that button.

Answer 3

Overdrive is the highest gear in your transmission. Your engine will turn at a lower RPM for a given vehicle speed. On the same note, your car will go faster for a given engine RPM. You'll get better gas mileage. Leave it in overdrive full time unless you are driving up a steep hill AND the transmission keeps hunting between overdrive and 3rd gear. This usually occurs around 45 mph. Then manually shift into 3rd gear.



Automatic transmissions work this way: When you select any given forward gear, you're telling the transmission NOT to shift into any higher gear. You will always start moving in 1st gear, then the transmission will automatically upshift into the next higher gear until it has selected the highest gear you've allowed with the shift lever.



Turning off the overdrive will have absolutely no effect on acceleration from a stop.



It's a Scion. It isn't a race car. Don't expect anything more.

Answer 4

Your car will have a faster top speed with the overdrive on. The overdrive does not kick in until you are shifting from drive to overdrive. Having it off will have no bearing on how fast you get to the speed that it kicks in. If you leave it off all the time you could damage the motor. When it kicks into overdrive it lowers your RPM's buy about 400 rpms. This has a bearing on your gas mileage. The lower your rpms are the less gas you will use.

Answer 5

We have to define fast. overdrive is a forth gear in a three speed transmission.Your car starts out in first gear and goes thru the gears until it reaches overdrive .Overdrive runs the motor slower so you can get better milage but will probably never reach top speed.third gear will probably acheive the same speed turning the motor faster giving you worse gas milage.If you have a tach. drive at 50 mile per hour and see what your rpms are in third gear then shift into overdrive at the same speed see how much less they are to go the same speed

Answer 6

well overdrive is mainly for gas mileage it is the only gear that is actually spinning faster that the engine .. it will be faster in overdrive if it has the power to push it but my guess is it doesn't but it wont make it any faster with it off

Answer 7

ROFLMAO!!!! You want to go fast in a Scion? It won't make a stick of difference in or out of overdrive. Once in "Overdrive", the engine doesn't have the torque to reach anywhere near redline of the engine. Out of "Overdrive" you'll reach redline, maybe, but be burning more fuel. You may have a slightly higher top speed out, but I doubt it.

Answer 8

With it on.



And you have a Scion XB. You can't ask about it being faster, as it's not "fast" in the first place.



As far as what overdrive does, go google it. Surely you know how to SEARCH, right?

Answer 9

It won't make any difference with the throttle wide open.

The purpose is to allow the engine to run at a lower rpm for better fuel economy when cruising.