Automatic transmissions are simple to use but complex to understand. Instead of having a piece of meat do all the work, advanced engineering takes care of the mundane task of shifting gears. It’s so simple that all the gears have been broken down into functions marked by P, R, N, D, L, or S, but what do they mean?
P = Park
This position on your gear selector literally parks your vehicle. The ‘P’ can often be found on the top-most part of your lever. In the case of a digital shifter, the park function of your selector can take quite a few forms. In the case of the Chery Tiggo 7 Pro and several BMW models, to engage the park function the driver needs to push a button in order to engage the park gear.
As to how it works, pressing the button or putting the lever into the park position engages what we call a parking pawl, and disengages the power from the engine This component essentially locks your transmission into place and keeps the wheels from rolling. Most cars with electronic parking brakes lock the rear wheels in conjunction with the parking pawl in one motion. For other cars, it’s advisable to engage the emergency brake first, then put your transmission into park.
R = Reverse
A lot of jokesters will say that R stands for “racing,” but that couldn’t be further from the truth. How can you go racing going the wrong way? In short, R stands for reverse. There are a bunch of gears that reverse the direction of your car’s travel.
Right below your park position, you will find reverse denoted by an ‘R.’ It is advised that drivers should first let the car come to a full stop first before engaging this transmission function.
N = Neutral
If you’ve driven a manual transmission, you will know that the centermost lever position indicates that no gear is engaged in the transmission. The same goes for automatic transmissions. Manufacturers often place the neutral function in the middle of all the other gears.
Putting your transmission in neutral may seem like a weird thing in an automatic transmission. For starters, if you want to come to a stop, all you need to do is hold the brakes to keep your vehicle in place. However, in order to take some load off your engine, it’s advisable to put your transmission in neutral and hold the brakes. More modern transmissions like dual-clutch or auto-gearshifts—as found in the Suzuki Dzire, disengage the engine’s flywheel and clutch even when the gear selector is in drive, however, you can still put your transmission into neutral if you think that you will be stopped for a modest amount of time.
D = Drive
You will surely need this function if you want to get anywhere. ‘D’ stands for drive, and this function engages all your transmission’s forward gears. Just hold the brake pedal, and then shift into this gear to get going.
L = Low
Now, below the drive position on your gear selector, you will find yet another transmission function. ‘L’ stands for low range, which will make your transmission hold the gear ratio in order to engage the engine brake. This transmission function limits your car’s speed so you don’t have to be too dependent on the brakes. Do note that this function doesn’t necessarily harm your engine.
The low function is a bit of a dying breed. With the advancement of transmission technologies, manufacturers have been slowly replacing the function with other letters which denote other functions. There are still cars that have this low function like the Mitsubishi Xpander with its 4-speed automatic transmission. However, even continuously variable transmissions (CVTs) like the one found in the Honda Brio and Civic, still retail the ‘L’ as these models don’t come with manual gear selectors.
S = Sport or M = Manual
Other cars, instead of an ‘L,’ will come with an ‘S’ or ‘M.’ Like a transmission’s low function, putting your gear selector in this position will allow you to select gears to engine brake. Note that you have to select a lower gear in order to engage the engine brake. This function allows the driver more control rather than have the transmission shift automatically. Applicable for more spirited driving or when more control of the engine is needed, Sport or Manual transmission functions in automatic gearboxes are ultimately more exciting for enthusiasts even if it doesn’t involve a clutch.