To understand what OverDrive mode is, let's take a look. It has several modes of operation, which you can directly control the "handle", or some of the modes are controlled by switches, so to speak "electrically". Based on this, it is clear that you can sort out the speeds in an automatic box with the selector itself in manual mode, or the box itself will determine the switching order.
The selector can be controlled in several modes:
- P - (parking). When the selector is moved to this position, the input shaft of the automatic transmission is blocked, that is, the rotation of the drive wheels will be in different directions due to the use of a differential. It follows that it is contraindicated in this mode.
- R - Reverse gear (rear). No explanation is required here. When the lever is moved to this position, an audible buzzer usually sounds.
- N - Neutral (neutral). As soon as the selector is in this position, the blocking of the output shaft of the "automatic machine" is turned off. In this mode, you need to tow the car or move "coasting", but subject to further compensation of speed to a complete stop. Switching from mode N to mode D on the move is prohibited due to excessive wear of the automatic transmission.
- D - The so-called Drive mode. It is used to move forward with subsequent gear changes in sequential order (1-2-3-4).
There are also modes 2 or 3, in which it is possible to move forward in two or three gears, respectively. Typically, such modes are included when overcoming difficult road sections, as well as for more effective engine braking.
Transmission system
- L - It is possible to move only in the lowest (first) gear. They are used when overcoming difficult road sections, during long descents. On the move, you cannot transfer the selector from position D to L, that is, you must start movement from it.
And now the most interesting thing is electronic modes. Let's consider one of them in more detail.
What is overdrive for?
Some automatic transmissions have an overdrive button on the selector lever. The question is - what is OverDrive technology for? In a literal translation from English, OverDrive means movement "on the engine", in simple terms - overdrive, the optimal variant of the car's movement is used based on engine speed and movement speed. For a simple car enthusiast it will sound like this: this mode is similar to direct transmission in, when the torque is transmitted from the primary shaft to the secondary shaft directly, bypassing the intermediate shaft (the gear ratio is 1: 1), usually this is the fifth gear. How to use overdrive, we will begin to explain from the moment it is turned on with the button:
activation of this function is controlled by the overdrive button on the automatic transmission. Enabling the OverDrive mode allows the use of the fourth gear in the mode of "soft blocking" of the torque converter, and before that, during acceleration, the box sequentially switches from first gear to fourth, up to blocking.
Note, when the overdrive button on the automatic transmission is pressed, the indicator is off, but the function is working.
When this button is disabled, the indicator on the instrument panel "o / d off" lights up in yellow or orange.
Moving in the mode of 1-2-3 gears, the o / d does not show its presence in any way. This mode is used when driving on high-speed sections, as a result of which engine noise is reduced and, most importantly, fuel consumption is reduced. When driving in areas with difficult road conditions or under load, it is better to disable OverDrive.
Video: Overdrive automatic transmission. How to use Overdrive and Kick-Down
An automatic box, which has an O / A mode in its asset, is equipped with a control solenoid, in the circuit of which a thermal sensor, a mode activation button and an indicator are included. That is, on a cold engine, you can turn on the O / D mode, the indicator will show it, but the mode will not turn on.
A little more about driving in this mode. If, when the overdrive mode is on, you simply release the gas pedal, the transmission will shift to an upshift, and the ride will take place at medium engine speeds. Keeping the pedal pressed at least slightly, the transition to an upshift occurs later, the revs will be correspondingly higher. It is clear that you will not understand the difference during overclocking. This difference will manifest itself when driving in the city in crowds and traffic jams. For example, when it is necessary to brake with the engine, this mode only interferes - the box goes to an increased one and the car rolls. Therefore - how to use overdrive? - the question is purely rhetorical.
The answer to the question - is OverDrive mode necessary? - seems to lie on the surface. Yes! - motorists who move sedately, without fussing, taking care of fuel economy and ecology, will surely say. No! - so say fans of dynamic driving, with frequent use of the kickdown mode (gas pedal to the floor). But I would like professionals to drive on the roads, even with an amateur license. Using this mode on highways and disabling it in the city and when driving on difficult roads, you will further extend the life of your automatic transmission. The controversial issues that arose about OverDrive were correctly characterized by one of the gearbox designers: laziness will move progress for a long time, it is thanks to human laziness that mechanisms are invented that make life even easier.
