Originally posted by: vital
i'd like to know when do you usually turn on/off your overdrive? what is it really used for?
Originally posted by: prodigy69
I don't know but vital has the same question as you.
Originally posted by: bolido2000
Overdrive is like 5th in manual transmission. IE, when is off you are locking out the 4th gear in a 4 speed transmission.
Just leave it on and forget about it. brake pads are not so expensive anyways![]()
Originally posted by: MiataGirl
overdrive is the gear in which the gear ratio is less than 1:1. In a 4 spd auto it'd be 4th gear, and in a 5 spd manual it's usually 5th gear. Some 6 speeds have both 5th and 6th gears in overdrive.
For example the Z28 with the 6-sp, has 5th gear at 0.74:1, and 6th at 0.50:1..this decreases the amount of power at that given gear, but improves gas milage.
BMW's tend to not have any overdrive gears in their 5-spds, which increases power in the highest gear, but decreases gas milage.
Usually you should leave od on to get better gas milage. If you leave it off though, and say you have a 4-sp automatic, your car will never shift into 4th. Even if is on though, flooring the gas in 4th will usually downshift for you anyways..
Originally posted by: thomsbrain
Originally posted by: prodigy69
I don't know but vital has the same question as you.
no i had a similar question to vital. he started this thread, not me.
which leads me to the next order of buisness. i figured out this threads screwing up thing. the clocks got set back on the AT server and now my posts show up "before" the first two before the switch.
Originally posted by: Millenium
Being that overdrive is the weakest gear in your transmission, if you have a fairly powerful vehicle you should never floor it in overdrive nor switch overdrive on until you are at a steady speed.
Originally posted by: Millenium
Originally posted by: MiataGirl
overdrive is the gear in which the gear ratio is less than 1:1. In a 4 spd auto it'd be 4th gear, and in a 5 spd manual it's usually 5th gear. Some 6 speeds have both 5th and 6th gears in overdrive.
For example the Z28 with the 6-sp, has 5th gear at 0.74:1, and 6th at 0.50:1..this decreases the amount of power at that given gear, but improves gas milage.
BMW's tend to not have any overdrive gears in their 5-spds, which increases power in the highest gear, but decreases gas milage.
Usually you should leave od on to get better gas milage. If you leave it off though, and say you have a 4-sp automatic, your car will never shift into 4th. Even if is on though, flooring the gas in 4th will usually downshift for you anyways..
Being that overdrive is the weakest gear in your transmission, if you have a fairly powerful vehicle you should never floor it in overdrive nor switch overdrive on until you are at a steady speed.
Originally posted by: MiataGirl
Originally posted by: Millenium
Being that overdrive is the weakest gear in your transmission, if you have a fairly powerful vehicle you should never floor it in overdrive nor switch overdrive on until you are at a steady speed.
well yeah, on a manual you're not going to shift into 5th gear if you're at 20mph. and in an automatic it's pretty much impossible.
i don't get what you're saying about flooring it in overdrive though. why shouldn't you ever floor it?
Originally posted by: thomsbrain
Originally posted by: Millenium
Originally posted by: MiataGirl
overdrive is the gear in which the gear ratio is less than 1:1. In a 4 spd auto it'd be 4th gear, and in a 5 spd manual it's usually 5th gear. Some 6 speeds have both 5th and 6th gears in overdrive.
For example the Z28 with the 6-sp, has 5th gear at 0.74:1, and 6th at 0.50:1..this decreases the amount of power at that given gear, but improves gas milage.
BMW's tend to not have any overdrive gears in their 5-spds, which increases power in the highest gear, but decreases gas milage.
Usually you should leave od on to get better gas milage. If you leave it off though, and say you have a 4-sp automatic, your car will never shift into 4th. Even if is on though, flooring the gas in 4th will usually downshift for you anyways..
Being that overdrive is the weakest gear in your transmission, if you have a fairly powerful vehicle you should never floor it in overdrive nor switch overdrive on until you are at a steady speed.
that would only be for manuals though. i assume autos can take care of themselves in terms of waiting to shift and kickdowns. since that's like what they do.
Originally posted by: Millenium
Originally posted by: MiataGirl
Originally posted by: Millenium
Being that overdrive is the weakest gear in your transmission, if you have a fairly powerful vehicle you should never floor it in overdrive nor switch overdrive on until you are at a steady speed.
well yeah, on a manual you're not going to shift into 5th gear if you're at 20mph. and in an automatic it's pretty much impossible.
i don't get what you're saying about flooring it in overdrive though. why shouldn't you ever floor it?
no, an automatic can be in fourth gear at 20 MPH but it depends on your gear ratio. Overdrive is a very weak band even when it is built with aftermarket parts. If you have a fairly powerful car, you should not be in the habit of flooring it in overdrive and wanting it to downshift. Now mind you I am talking about cars with over 300HP or ft lbs of torque. Not only is this supported by Peformance Automatic, Lentech, and Jerry W.(chief engineer of several ford auto trannys), but you have my word that I know what I am talking about.
Originally posted by: MiataGirl
Originally posted by: Millenium
Originally posted by: MiataGirl
Originally posted by: Millenium
Being that overdrive is the weakest gear in your transmission, if you have a fairly powerful vehicle you should never floor it in overdrive nor switch overdrive on until you are at a steady speed.
well yeah, on a manual you're not going to shift into 5th gear if you're at 20mph. and in an automatic it's pretty much impossible.
i don't get what you're saying about flooring it in overdrive though. why shouldn't you ever floor it?
no, an automatic can be in fourth gear at 20 MPH but it depends on your gear ratio. Overdrive is a very weak band even when it is built with aftermarket parts. If you have a fairly powerful car, you should not be in the habit of flooring it in overdrive and wanting it to downshift. Now mind you I am talking about cars with over 300HP or ft lbs of torque. Not only is this supported by Peformance Automatic, Lentech, and Jerry W.(chief engineer of several ford auto trannys), but you have my word that I know what I am talking about.
Missed that powerful vehicle part in your post..missed it in the first post of the thread too, and for that reason I didn't think the poster was asking specifically about vehicles with 300hp/ft-lb torque, nor did he mention only automatics, and I really don't think he said anything about performance shifters. So what does your post have anything to do with the thread?