When to shift gears in an automatic car

Have you ever wondered what those letters on an automatic transmission gear shifter mean? Well, you’re not alone. There are more than 10 million automatic-transmission operated vehicles in the United States alone sold each year. The automatic transmission is a reliable, hydraulically-operated system that applies the power coming from the engine to your drive wheels. Each letter or number listed on the transmission gear shift represents a unique setting or task for the transmission. Let’s dive into the automatic gear shift meaning so you’ll understand what each letter or number means.

Introducing PRINDLE

On most US and imported cars featuring an automatic transmission are a series of letters that spell out P – R – N – D – L. When you sound them out, it’s phonetically called “Prindle.” In fact, that’s what most engineers call the automatic gear shifter configuration, so it’s a technical term. Each letter stands for an individual setting within the automatic transmission. Depending on the type of vehicle you own, it’s also possible that you might see an “M” or a series of numbers — likely 1 through 3. To simplify things, we will break down each letter listed on most automatic transmissions.

What does the P mean on an Automatic Transmission?

The letters on an automatic transmission are often described as an individual “gear” setting, but that’s a bit misleading. It’s actually an activation setting. The gears inside an automatic transmission are hydraulically shifted and can range from three to nine speeds while in a forward ‘gear’.

The “P” on an automatic transmission stands for the PARK setting. When the gear shifter is in park, the transmission ‘gears’ are locked, which restricts the wheels from being able to spin forward or backward. Many people use the park setting as a brake, which is a primary purpose for this transmission setting. However, most vehicles also require the car to be started while the transmission is in the “PARK” setting for safety purposes.

What does the R mean on an Automatic Transmission?

The “R” stands for REVERSE, or the gear selected to drive the vehicle backward. When you shift the gear lever from P to R, the automatic transmission’s reverse gear is engaged — which spins the drive shaft backward, allowing the drive wheels to spin in ‘reverse’. A car can’t be started in reverse gear, as it would be very unsafe to do so.

What does the N mean on an Automatic Transmission?

The “N” is an indicator that your automatic transmission is in NEUTRAL or a free spinning mode. This setting releases the gear(s) (forward and reverse) and allows the tires to spin freely. Most people do not use the N setting unless their car engine will not start and they need to push it or have the vehicle towed.

What does the D mean on an Automatic Transmission?

The “D” stands for DRIVE. This is when the automatic transmission ‘gear’ is activated. As you accelerate, the drive gear will apply power to the wheels and progressively shift into higher ‘gears’ as the engine RPM reaches the desired level. As the vehicle begins to slow down, the automatic drive gear will down-shift to lower gears. The “D” is also commonly referred to as ‘overdrive.’ This is the top ‘gears’ setting on an automatic transmission. This gear is used on highways or when the vehicle is driving at the same RPM for extended road trips.

If your automatic transmission has a series of numbers after the “D” those are manual gear settings for the forward gear operation — with 1 being the lowest gear and larger numbers representing higher gears. They can be if your regular D gear isn’t working, and when going up and down steep hills to provide more engine braking.

• D1: Increases torque for difficult terrains like mud or sand.
• D2: Aids the car in uphill climbing, such as hilly roads, or provides a quick engine boost similar to its function on manual transmissions.
• D3: Sometimes shown as an OD (overdrive) button instead, D3 revs the engine for efficient overtaking. The overdrive gear ratio causes the tires to move faster than the engine spins.

What does the L mean on an Automatic Transmission?

The final common letter on an automatic transmission is the “L,” which indicates the transmission is in a low drive gear. Sometimes the “L” is replaced with the letter M, meaning the transmission is in a manual shifted option. This setting allows the driver to manually shift the transmission by using paddle shifters located on the steering wheel, or another action (usually to the left or right of the automatic gear lever). For those with L’s, it’s a setting used for climbing hills or trying to navigate poor road conditions — such as being stuck in snow or mud.

As each automatic car is unique, some of them will have different letters or numbers listed on the gear shift lever. It is recommended to read and review the vehicle owner’s manual (usually located in the glove box) to ensure you use the correct gear setting for the right application.

Many of us grew up learning how to drive stick-shift cars. We got used to smoothly changing gears up and down as necessary while we were driving. The question is, with manual transmissions becoming basically extinct, can you change gears while driving in an automatic car? We have searched for the answer to this question so that you don't have to!

You can manually change to some gears while driving an automatic car. Other gears you should never switch to unless you are completely stopped as it can severely damage your engine. Most modern cars thankfully won't let you switch to some gears while driving to stop any mechanical disasters. For the most part, automatic cars up and downshift for you so you don't have to worry about it. 

Automatic cars all have varying shifters and gears that you can use. There is a wide variety of different "modes" that come with automatic cars that have different uses. It is very important to know the limitations of shifting with your specific car. If you do it wrong, it can cost you a lot of money and even more stress later on. Keep reading down below so you can know the complete capabilities of your automatic car's transmission!

Before you continue reading, let us say we hope you find the links here useful. If you purchase something through a link on this page, we may get a commission, so thank you!

Shifting Your Automatic Car While Driving

Depending on what gear you're trying to get to, you're even encouraged to shift your car while driving. You just have to know when those situations are. The transmission is no different than any other part of your car. You want to use it properly, and not wear it out any faster than you have to.

How Do You Manually Shift An Automatic Transmission?

Before talking about the ins and outs of shifting while driving an automatic car, it's important to know how to. Depending on your car, the shifter may have a button of some sort on it that you need to press to move the shifter. If this is true for your car, then press the button before shifting. Then you simply have to move the shifter to the desired gear. You may want to let off the gas while doing this. Your car should also, thankfully, restrict which gears you can do this with while driving. 

What Gears Can You Shift To While Driving An Automatic?

This can differ depending on the gear modes that are available in your car. Usually, cars will have a sport mode or economy mode, or some variations of those. You can and should shift to those while driving but only during the appropriate times. They are meant to optimize your car's performance.

However, if you don't use them at the appropriate times, shifting them can hurt your car. You should also be able to shift to neutral when needed, like if your car dies on the road while driving. 

What Gears Shouldn't You Shift To While Driving?

This might seem like common sense, but for the well-being of your car, it's important to point out. You should never try to shift into park or reverse while driving. As mentioned above, the majority of automatic cars on the road today won't let you do this anyway. Which is good because it could severely damage your transmission.

You shouldn't even switch in and out of these two gears when moving at all. Chances are your car will let you switch from reverse to drive while moving slowly. Even shifting between these gears at a low speed will wear down your transmission faster. 

Do You Ever Need To Shift While Driving An Automatic?

For the most part, not really. Automatic transmissions are designed to do their job more efficiently on their own than with us helping. That's why manual transmissions aren't really around anymore. Automatic ones do a better job at shifting than any human can.

You can use the driving modes mentioned above when it is appropriate to do so. Even with those, you should exercise caution so that your transmission doesn't see any unnecessary wear from it. 

More Automatic Transmission Questions

Learning if you can shift your automatic car while driving is just one piece of the puzzle. It's important to know in detail when and how it's appropriate to use that shifter while driving. Especially since many individuals aren't even sure what those extra letters next to the shifter even stand for. 

What Is S Mode In An Automatic Car?

S mode stands for "sport" mode. Even if you don't have a fancy sports car it may still be handy to you. Sport mode does a few different things that change your driving experience. The first thing it does is change when your automatic transmission decides to shift. Usually, automatic transmissions shift at fairly low RPMs. Sport mode makes it shift at a higher RPM. This changes the performance level of the car and gives many a smoother driving experience.

It also affects the suspension and handling capabilities. This is why it can be useful for navigating winding or twisting roads. Like when you're driving through mountains for example. It makes handling your car and normal speeds a bit more comfortable in these areas. 

Can You Shift From D To S While Driving?

Yes, you can shift from drive to sport mode while driving. This should only be done in situations like the ones explained above. You also want to avoid making this transition while completely pressing down on the gas pedal. This might be damaging for the transmission. Your car's computer should stop anything damaging from happening in this instance but better safe than sorry. 

How Do Automatic Cars Know When To Change Gears?

A lot goes into making an automatic transmission work the way that it does. Basically, when the RPM of your car gets to a certain accelerating speed it knows when your upshift. Also, when the RPM gets low enough, your transmission knows when to downshift. The transmission has sensors in it that tell it when these points have been hit so it knows when to shift. 

Why Does My Car Jerk When Shifting Gears With An Automatic Transmission?

Unfortunately, this is a fairly common problem with automatic vehicles. This can mean that there is already a problem with your transmission, or if you don't fix it soon there will be. One of the leading causes of this is that your car is low on transmission fluid. Either that or the fluid is very old and dirty and needs to be changed. There may also be a part inside of the transmission that is going bad. If it's not the fluid then it will save you a huge problem and bill later on if you take it into the shop now. 

Is There Anything You Can Do If You Really Want To Manually Shift?

Aside from getting a specially made or older manual transmission car, there is another option. Many newer automatic cars come with the option to manually shift them while driving! If the car has this, it will show a spot next to your shifter with a plus and minus sign. Sometimes there will also be an "m" next to them. Putting your automatic transmission into this mode will allow you to upshift and downshift on your own! 

Finishing Up

You can change gears while driving your automatic vehicle. Your car thankfully shouldn't let you shift to the most damaging gears like reverse and park. When shifting to the other options, it's important to know when it's the appropriate time to do so. Not shifting in the correct situations can easily start to damage your automatic transmission. Now that you know how to use your automatic transmission as effectively as possible, all that's left is to take a road trip!

For more transmission information make sure to click on the links below:

When Should You Check Transmission Fluid?

What Pickup Trucks Come In Manual Transmission?

Does Toyota RAV4 Have CVT Transmission? [Various Models Reviewed]