How To Check Transmission Fluid: A Step-by-Step Guide

Maintaining your vehicle's transmission is crucial for its overall performance. One of the easiest yet most important aspects of transmission maintenance is learning how to check transmission fluid. Transmission fluid ensures that your vehicle's transmission operates smoothly by lubricating its moving parts and preventing overheating. If you want to avoid costly repairs and keep your car running efficiently, it’s important to regularly check your transmission fluid.

In this blog post, we’ll show you exactly how to check transmission fluid level and the steps involved, especially for automatic transmissions. We'll also dive into the importance of knowing how to check automatic transmission fluid level and what to look for during your inspection.

Why is Checking Transmission Fluid Important?

Before we jump into the how-to, let’s understand the significance of transmission fluid. Transmission fluid plays an essential role in your car’s operation. It keeps the transmission cool, reduces wear on moving parts, and facilitates smooth gear shifts. Without enough transmission fluid or with poor-quality fluid, your vehicle can experience overheating, erratic shifting, or even transmission failure.

Checking the transmission fluid regularly can help you spot problems before they escalate, saving you from costly repairs in the future. Now that you know why it’s important, let’s take a closer look at how to check transmission fluid.

How to Check Transmission Fluid Level

Checking the transmission fluid level is a relatively simple task, but it's important to follow each step to get an accurate reading. Here's how to check transmission fluid level:

1. Park the Vehicle on a Level Surface

To get an accurate reading of the fluid level, it's essential to park your vehicle on a flat, level surface. This will ensure that the fluid level is correctly measured, avoiding any inaccurate readings caused by the car's angle.

2. Start the Engine

For most automatic transmission vehicles, how to check automatic transmission fluid level requires that the engine be running. This helps the fluid expand and gives a more accurate reading. However, some older models or manual transmissions may require the engine to be off. Make sure to refer to your vehicle’s owner’s manual for specific instructions regarding your car model.

3. Locate the Transmission Dipstick

The transmission dipstick is typically located near the back of the engine bay, often near the transmission itself. It’s usually a brightly colored handle, often yellow or red, to make it easy to spot. If you’re unsure of its location, consult the owner’s manual for guidance.

4. Pull Out the Dipstick and Wipe It Clean

Once you’ve located the dipstick, pull it out and wipe it clean with a cloth or paper towel. This step ensures that you’re not reading a false level caused by residue left from the previous check.

5. Reinsert the Dipstick and Pull It Out Again

Insert the dipstick back into the tube fully and then pull it out once again to check the fluid level. You’ll notice marks on the dipstick indicating the fluid level. There are typically two lines, one for “full” and one for “low,” or there may be a set of dots or holes indicating the correct range for fluid levels.

If the fluid level is between the two marks, your transmission fluid is at the right level. However, if the fluid level is low, you'll need to add more fluid to bring it back to the correct level.

6. Inspect the Fluid’s Condition

While you’re checking the level, also take a moment to inspect the fluid’s condition. Healthy transmission fluid should be clear and bright red. If the fluid is brown or has a burnt smell, it could indicate that the fluid is old or that the transmission is experiencing problems. In such cases, it may be necessary to change the fluid or consult a mechanic.

7. Add Fluid if Necessary

If you find that the fluid level is low, you’ll need to add the correct type of transmission fluid. Be sure to use the type specified in your owner’s manual. To add the fluid, use a funnel to pour it into the dipstick tube, checking the level as you go. Add small amounts of fluid and recheck frequently to avoid overfilling the transmission.

How to Check Automatic Transmission Fluid Level: Special Considerations

For automatic transmissions, how to check automatic transmission fluid level follows a similar process but with a few key considerations. Most automatic transmissions require that the engine is running when you check the fluid level. This is because the transmission fluid expands as the engine heats up, and a cold engine will not give an accurate reading.

In addition, some newer cars may have a sealed transmission system, meaning they don’t come with a dipstick at all. Instead, they may require special tools or expertise to check the fluid. If your car doesn’t have a dipstick, you may need to take it to a mechanic or dealership to have the fluid checked.

Signs That You Should Check Your Transmission Fluid

While regular fluid checks are important, certain signs can indicate it’s time to check your transmission fluid level sooner:

1. Slipping Gears: If your vehicle hesitates or struggles to shift gears, low transmission fluid could be the cause.

2. Delayed or Rough Shifting: If your car takes longer than usual to shift gears or does so roughly, it may be due to low or contaminated fluid.

3. Unusual Noises: Grinding, whining, or clunking noises can indicate a transmission problem, potentially related to low fluid.

4. Warning Lights: Some vehicles have a transmission warning light that will activate if the fluid is low or if there’s an issue with the transmission.

5. Burnt Smell: A burnt smell from the transmission is a sign that the fluid is old and may need to be changed.

How Often Should You Check Transmission Fluid?

It's important to check your transmission fluid level regularly, especially if you drive under heavy conditions such as towing, off-roading, or frequent stop-and-go traffic. Generally, you should check your transmission fluid every 30,000 miles or every two years, but always refer to your vehicle’s owner’s manual for specific recommendations.

Conclusion

Knowing how to check transmission fluid is an essential skill that can help prevent major transmission issues and keep your car running smoothly. Regularly checking the fluid levels and condition ensures that your transmission operates as it should and helps catch potential problems early. Whether you’re learning how to check transmission fluid level for the first time or just need a refresher, following these steps will ensure your car’s transmission stays in top condition.