How to Check Your Transmission Fluid

When your car gets serviced, one component of your vehicle that will be checked is your transmission fluid.

Your vehicle’s transmission fluid lubricates the moving parts inside the gearbox, preventing overheating and ensuring seamless gear shifts.

Low or dirty fluid can lead to sluggish performance, rough shifting, or even costly transmission damage.

Fortunately, checking the fluid level and condition only takes a few minutes and can save you from expensive repairs down the line.

In this guide, we’ll walk you through the steps to check your transmission fluid properly, whether your vehicle has a dipstick or a sealed transmission system.

How often should you check your transmission fluid?

You should look to be checking your transmission fluid around once a month.

This ensures that you can catch any potential issues early, such as low fluid levels or contamination, which could affect your vehicle’s performance.

Regular checks help maintain smooth gear shifts, prevent overheating, and extend the lifespan of your transmission.

If you notice the fluid is low, dark, or has a burnt smell, it may be time for a top-up or a full fluid change.

Always refer to your vehicle’s manual for specific guidance on checking and maintaining transmission fluid levels.

What you’ll need:

• A clean cloth or paper towel – To wipe the dipstick and get an accurate reading
• Gloves (optional) – To keep your hands clean, especially if the fluid is dirty
• A well-lit area – Ensuring you can clearly see the dipstick markings and fluid condition
• Your vehicle owner’s manual – To help locate the dipstick and check manufacturer-specific recommendations

Step 1: Park vehicle on level surface and start engine

Park your car on a level surface to ensure an accurate reading of the transmission fluid level.

Start the engine and let it idle for around 5-10 minutes so the fluid reaches its normal operating temperature.

Most vehicles require the engine to be running when checking transmission fluid, but always check your owner’s manual for specific instructions.

Step 2: Open bonnet and locate your fluid dipstick

With the engine running, open the bonnet and find the transmission fluid dipstick. It’s usually marked with a yellow or orange round handle, similar to the oil dipstick.

If you’re unsure where to find it, refer to your vehicle’s manual.

Step 3: Remove dipstick and wipe clean

Carefully pull out the dipstick and use a clean cloth or paper towel to wipe away any residue. This step is important because transmission fluid can cling to the dipstick, making the initial reading inaccurate. Ensure the dipstick is completely clean before reinserting it. If the fluid on the dipstick appears very dark or has a burnt smell at this stage, it could indicate that your transmission fluid is due for a change.

Step 4: Check markings on dipstick

Reinsert the dipstick fully, then remove it again to check the fluid level. The dipstick will have two lines or dots that indicate the safe fluid range. The fluid level should be between these markings. If the level is below the lower line, the transmission may be running low on fluid, which can cause poor shifting performance and potential damage. Also, inspect the colour and consistency of the fluid—it should be a clear reddish colour. If the fluid looks dark brown or has metal particles, it may need to be changed.

Step 5: Clean dipstick and insert it back in your vehicle

After taking the reading, wipe the dipstick clean again to remove any excess fluid before securely reinserting it back into the tube. Make sure it is fully seated to prevent contamination or leaks. If the fluid level was low, check your owner’s manual for the correct type of transmission fluid before topping it up.

If by now you’re still unsure about your fluid’s condition or level, consider consulting a professional mechanic at your local garage to avoid any transmission issues.