Why the gears sequence in automatic transmission cars is almost always PRND?

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And why R is before D, making the driver behind you think you are backing up?

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16 Answers

Anonymous 0 Comments

In the early days of automatic transmissions reverse was the last position or at the bottom. It was changed due to a government regulation.

https://www.curbsideclassic.com/automotive-histories/automotive-history-the-mysterious-disappearance-of-the-chrysler-pushbutton-automatic-a-government-conspiracy/

Anonymous 0 Comments

In the early days of automatic transmissions reverse was the last position or at the bottom. It was changed due to a government regulation.

https://www.curbsideclassic.com/automotive-histories/automotive-history-the-mysterious-disappearance-of-the-chrysler-pushbutton-automatic-a-government-conspiracy/

Anonymous 0 Comments

You want the drive gear to be as far away from the reverse and park gears as possible. On not-very-much-older automatics it was entirely possible to shift from drive to reverse or park while in forward motion, which annihilated the transmission and was very dangerous to the passengers. A lot of modern cars have a locking mechanism that engages to prevent this but that can fail of course. Having the order like this is not only safe, but it is consistent across vehicles, making driving a new vehicle east to pick up.

Anonymous 0 Comments

You want the drive gear to be as far away from the reverse and park gears as possible. On not-very-much-older automatics it was entirely possible to shift from drive to reverse or park while in forward motion, which annihilated the transmission and was very dangerous to the passengers. A lot of modern cars have a locking mechanism that engages to prevent this but that can fail of course. Having the order like this is not only safe, but it is consistent across vehicles, making driving a new vehicle east to pick up.

Anonymous 0 Comments

so, it starts from the order Reverse-Neutral-Drive, which makes sense, one-direction | no-direction |opposite-direction.

now we have to add park, well you could put it right next to drive, but it’s not a good idea as it could make it easy to accidentally shift to park while driving which isn’t a good thing, so the only other reasonable place is before reverse

also this makes it so after drive you can have L or S, which are just froward with a slight twist

Anonymous 0 Comments

so, it starts from the order Reverse-Neutral-Drive, which makes sense, one-direction | no-direction |opposite-direction.

now we have to add park, well you could put it right next to drive, but it’s not a good idea as it could make it easy to accidentally shift to park while driving which isn’t a good thing, so the only other reasonable place is before reverse

also this makes it so after drive you can have L or S, which are just froward with a slight twist