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Do You Add Transmission Fluid While the Car Is Running?

Cars require various essentials to run properly. One of them is the transmission fluid. Transmission fluid is an important element for a car because it helps the car’s gearbox, also known as transmission, run smoothly from gear to gear.

Transmission fluid is important for a car to keep its transmission operations running smoothly without any hassle. Let us help you know if you can add transmission fluid while the car is running and other necessary information related to this.

Do you add transmission fluid while the car is running?

Depending on your car’s transmission type, you should add transmission fluid while the car is running. Adding transmission fluid while running the car helps you to understand the proper level of how much fluid you have by using the dipstick as the fluid expands when the engine runs.

Like all fluids, transmission fluid expands when it absorbs heat. You can’t identify the proper amount of transmission fluid in your car’s transmission as the transmission fluid gets compressed when it is cold.

In the transmission system, the torque converter must be submerged in transmission fluid when the car is running. But the level of transmission fluid decreases as you turn your car off. Thus, you can’t find the proper level of transmission fluid in your car.

Due to these reasons, you should add transmission fluid while the car is running to understand the proper level of transmission fluids in your car by not overfilling it.

How long should a car run before checking transmission fluid?

A car should run for at least 2 – 3 minutes before checking the transmission fluid. You should keep your car in parking mode or neutral mode while doing this and always keep your hand brakes on. When you keep your car running, make sure not to overheat by throttling it.

During the cold season, you should run your car more than the usual times to get the proper reading of your transmission fuel level. As the temperature of the transmission fluid stays very low during those times, it takes more time to get warm.

How do I add transmission fluid to my car?

After using your car for 30000 – 60000 miles, you may have to add or change the transmission fluid. Adding or changing transmission fuel is very easy and you can do it by yourself. Let us look into the steps of adding transmission fluid to your car:

Purchase the right transmission fluid:

Purchasing the correct transmission fuel is crucial. If you use the wrong transmission fuel, your car can be damaged. Check your car’s manual for the proper information about the type of transmission fluid that you will need.

Turn off your car and set its transmission in parking or drive mode:

Keep your car on ignition. Also, keep your cars transmission in parking or drive mode. Do not forget to set your parking brakes too. Keep the car running for 1 – 3 minutes depending on the environment.

Open the dipstick and check your transmission fluid level:

Open the front hood of the car. You will find a dipstick hole in your engine. If you can’t find it, kindly check your car’s manual for details.

After you find it, open it by turning it a bit and get the dipstick out from the hole. Clean the dipstick and again put it in the hole. Get the dipstick out now and check the level of transmission fluid. If the fluid seems low, you must add transmission fluid.

Insert a funnel in the hole:

Get a longer funnel so that you can properly get the transmission fluid in the hole. Insert the funnel properly so that you can start adding transmission fuel to your car.

Add the transmission fuel:

Start filling the transmission fuel using the funnel. Fill slowly and often check using the dipstick so that you do not overfill.

It may take you about ¼ quarts to just top off or take about a maximum of 13 quarts to fill the whole transmission if you decide to change the whole transmission fluid.

Change transmissions while filling:

While you are checking if the car has filled or not, cycle through all the transmissions from your driver’s seat so that the transmission fluid can run through all the gears properly.

This will help you to get a proper reading of your transmission fluid level as well.

Properly seat the dipstick after finishing:

After you finish filling your car with transmission fluid, remove the funnel and seat the dipstick properly. Check if the dipstick has seated properly or not. If it doesn’t seat properly, you may end up wasting your transmission fluid.

Can you add transmission fluid while the car is hot?

Yes, you can add transmission fluid while the car is hot. While your car is hot and is at optimal temperature, it is said to be the best condition to add transmission fluid to your car.

When the car is hot, it gives the correct reading of your transmission fluid and you can add the required amount of transmission fluid to your car.

Can you add transmission fluid while the car is off?

Yes, you can add transmission fluid while the car is off, but you may damage your car in this process. You may end up overfilling your car with transmission fluid. Your transmission box may get jammed or not act as it should be when you turn your car on.

Why should you check transmission fluid when the engine is running?

It is advised by almost all car manufacturers to check your transmission fluid when the engine is running. Let us go through the reasons why we should do this:

Fluids expand when it gets heated:

All fluids expand when it absorbs heat. Transmission fluid is no exception. Thus, you can get the correct levels of your available fluid levels when the car is running.

Transmission fluids do not stay in the pan:

In the compartment, the torque converter stays submerged under transmission fluid when the engine stays running. But when it’s turned off, most of the transmission fluid stays at the bottom pan, as a result, you may not get a proper reading.

How do I know if my car needs transmission fluid?

There are a few ways to know if your car needs transmission fluid. Let us discuss the ways of it:

Warnings on your dashboard:

When your car needs transmission fuel, it will show you a warning in your dashboard. The transmission fluid temperature will be higher than usual when your car needs a refill of transmission fluid.

Burning smell from your car:

When your car is running low on transmission fuel, you may get a burning smell from your car. This happens due to a lack of lubricant in the transmission parts.

Having difficulties in shifting gears:

If you find your gears hard to shift, this may indicate that your transmission fluid levels are running low and you need to add some fuel as soon as possible.

Transmission fluid puddles under the car:

If there is a puddle of transmission fluid under your car after keeping it in the parking lot for some time, it might indicate leakage in your transmission system. Likewise, you can also think that your car may be running low on transmission fluids as well.

How often do you have to put transmission fluid in your car?

You have to put transmission fluid in your car after every 30000 – 60000 miles depending on your usage and car manufacturer.

For cars with a manual transmission, you need to check your fluid levels after every 30000 – 60000 miles and change or add transmission fluid according to your car’s needs.

Likewise, for cars with automatic transmission, you have to check after every 30000 miles if you have to put transmission fluid or not. But even after checking, cars with an automatic transmission may not require a change or addition of transmission fluids due to its efficiency.

How much transmission fluid to add if empty?

Depending on your car, about 4 – 14 quarts of transmission fluid are to be added if empty. Cars with manual transmission require 4 – 10 quarts of transmission fluid. Whereas, cars with an automatic transmission require 14 quarts or more.

Kindly refer to your car’s manual for the proper information or consult with your local car mechanic. If you find indications of low transmission fluid in your car, you should add it as soon as possible. It may cause harm to your car if you do not add transmission fluids.

Final Thoughts

It is necessary to add transmission fuel while the car is running. Examining the amount of transmission fluid is a vital part of car maintenance. It gives you a proper overview of how much transmission fuel your car needs and also helps you to properly spread the fluid in your transmission box.