sorry if this been post b4... bad mood cant take my time and search patiently... was arguing with my sister about my old car... she claims the dealer told her all cars that have overdrive button... ppl should use that whenever they r driving local...or else the transmission is gonna be wasted sooner.. Is that true?? i remember reading the forum b4 about OD serving as 3rd gear or something... but wut's the pt of OD? plssssss dont be annoyed and help b4 i explode from pissing myself off at the world....:mad:
Driving an automatic with OD on... in local
- Thread starter Vicocola
- Start date
Yes, put simply (it is 4th gear).Patio said:
It's a final gear in the car. OD is for fuel economy and engine life (it lowers revs). From "How Stuff works: Overdrive":
From this page.
flat_black
Member
"Overdrive", as it were, refers to two things, but in general, it acts as a last gear, presumably any gear with a ratio of 1:1 or lower. In some automatic transmissions, it's simply an extra gear, but in most older Volvo's (1980's), it's an extension of the transmission, as it is in some cars. Volvo's have the overdrive in both the manual and automatic transaxle, however, and in the automatic, it has a button to push to disengage last gear; In the manual, it's used to shift INTO overdrive from fourth. That being said, it's not always a fourth gear. The 4EAT tranny in several Subaru's, and some Mazda's, I beleive, is in fact a five speed transmission (4 gears, plus overdrive). But simply stated, overdrive is any gear or extension of a transmission that pushes the ratio to 1:1 or lower.
Just keep it on, never turn it off. You dont "use" it, the computer/AT decides to use it. It does it automatically when it feels like it, which is when you are traveling at a higher rate of speed (which can be as low as 35mph) and you are not accelerating. It will shift into OD to lower the revs, which of course saves gas and extends the life of the engine. All new cars (I'm generalizing just a bit), and all old cars for a long time have OD. If you were towing something (which you will NOT in a MazdaCameleon3 said:
) you might want to turn OD off to keep the increased torque of the lower gears. If you thought the number 4 was unlucky, you might want to turn the OD off. 
Turn it on, keep it on, dont freakin' worry about it.
OD has no detrimental effect, it is just a final gearing (actually not a "gearing" truly, because you are going straight through to the driveshaft). As I said before it just gives your AT the option to use that last gear. city, highway, hot, cold, red car, blue car, just keep it on and forget about it.
o ic... thx for the info... i hope my sis read this and will be satisify... blaming me not turning overdrive off driving around in the city and weaken the transmission or some BS... btw wut about driving at high rpm b4 switching gear... as long as i dont redline it... it should deal no damage to the transmission or engine or wutsoever rite?
It doesn't hurt to keep it off while in the city if traveling under like 3000 rpm in thrid. Not sure what speed this is on the p5, but if the OD just barely kicks in and then you start braking for a stop or traffic, it would've been easier on the tranny to have not shifted. And..
Not sure I understand, but if you mean revving the engine higher before switching gears, it will decrease the engine life a bit more, but it's probably negligable if going to less than like 4k.
i always rev it up to like 5... coz it has no hp... 107... 1.6L...Correct me if I'm wrong. I was told that if you are driving in a traffic, or driving in any condition that inovlves moving and stopping, then it is best to have OD off.
Hence when OD off, it drops to 3 gears instead 4; therefore, it takes higher rpm for each gear to switch to the next. Thus, there is less gear switching when the car is moving and stopping.
Hence when OD off, it drops to 3 gears instead 4; therefore, it takes higher rpm for each gear to switch to the next. Thus, there is less gear switching when the car is moving and stopping.
thunderb0lt
Member
When you turn O/D off, the tranny computer makes u stay in each gear longer. It's better when u are crawling in stop-n-go traffic on the freeway....less shifting for the tranny.
