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Overdrive Question

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15+ Year Contributor
Jun 23, 2004
Malibu, California
I know i should have bought a 5 speed, but when you find a 97 GSX with only 64K, you can't pass that up even if its an auto. my question is what exactly is overdrive? When should i use it? And how much faster does it make the car go? Also, does it effect gas mileage?
You really only need to use it at highway speeds. It gives you taller gears for better gas mileage on the highway.
Yes, its like the 4th gear when the button is activated. Its tight cause u can also drop gears as you would in a manual kinda. Like be driving at like 50-60mph and hit Overdrive then hit it off watch those rpms shoot up when its disingaged. Its like shifting haha kinda :D But yeah dont worry man i was in ur same position where i couldnt pass up a car even if it was auto. They got mass potetial and can be made jsut as fast as a manual if you mod it right. Plus its reliable too no worries on broken clutches and crankwalk..Well i never heard of crankwalk on an auto that is. But yeah check out the automatic forums and good luck with it.
Nothing wrong with an automatic. Especially when it get icy and slick, or on trips to Frisco. The odor from sintered clutch is quite nauseating.

Moved to A/T.
Your first missconseption with thinking an auto is all that bad. Auto's can be made to be a lot better than any manual out there.

With the auto being built right you will shift faster than any manual, and have consistant launches every time.

Ever been to a stop light, you look over at the Honda next to you, he is revving his motor, you put your foot on the brake, bring your RPMS up, and when he launches he drops his clutch to hard, lets it out to fast, to slow, spins his tires, bogges it down, and ever single time you launch with no problems...

Even better the same above, but this time eat your big mac, talk on your cell phone, and give the finger to the guy as you blow his doors off....LOL

On the original topic though....O/D keep it off in city driving under 40mph. O/D is your cruising gear not your race gear....
O/D drops your RPMS that equals better gas milage.

Again congrats on your auto GSX
The 4th gear end clutches are actually rotating while still in third gear (with OD button on). This is why DSM trans have failed end clutches. I leave it off until I'm on the highway and hear the RPM point where I need to put it on, then just cruise with it. If I need to pass quickly, I'll either step on the gas quickly and hard enough to downshift, or just take OD off.
were talking about the auto in the gsx right?... i drive an automatic GS with 106k and im on my third tranny, and i know what your thinking, but honestly i am not one to be hard on my car.
I have seen someone dyno 371 HP to the wheels on a GSX on a stock tranny. So i would say there pretty strong.
changing rotation speed puts some stress on the engine. of course it is not good to hit that little button on off on off on off all the time. same as redlining your car. don't do it too often you'll be fine. i do it when i get on/off the freeway.
I have read in one of the technical manuals you are to only shift in to O/D if u are going 50 or over. Otherwise it wears on the tranny and engine. Also turning the button on and off is like shifting from drive into 2 and back into drive over and over again. its is HARD on the tranny. You will wear it out that way not to mention its hard on the engine. O/D is for highway driving and gives u much better gas mileage. Keep O/D off while driving around in town.
so let me get this right...... i drive city 65-70mph with some runs to 80 and i should keep OD off and get better gas milleg???.... isnt it the other way, casuse w/ OD on its lower RPM so better gas millege i thought :confused: :confused:
ok...... here's the deal, when OD is "ON" engine rotates at a slower speed while producing the same output to the wheels however, at a lower torque (low rpm = lower torque). to save gas, turn OD "ON" ie. on the freeway. while in the city, you can still leave it on it'll still give you better gas milage. but general speaking, while you're street racing and want the maximunm torque always turn OD "off". if you're driving pass 80mph and noticing you're redlining, that's when you switch OD back on. OD functions as your 4th gear.
I think he meant to turn the O/D off light, off. :)
ok....just listen.
"O/D off" = cluster light on = more power/worse mileage.
"O/D on" = no light on cluster = less power/better mileage, used for freeway speeds.
All that's mentioned above is correct. I just want to add that in our motors, when the OD is on, and we are not driving at speeds where the 4th gear kicks in, the endclutches start to spin in 3rd. This is why our end clutches go bad, pre-mature wear. I leave mine off until I feel it has to go on.
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