Mazda 3 Transmission Fluid Change Guide

While Mazda markets its ATF as “lifetime,” most experts recommend changing it between 60,000 and 100,000 miles for optimal performance. Extreme driving conditions may necessitate earlier changes.

Here is how to do a quick Mazda 3 Transmission Fluid Change:

Mazda 3 Transmission Fluid Change 6 Steps Guide

1: Preparation

Gather the Tools and Supplies:

Before starting, gather all the necessary tools and supplies. Here is a list of what you are going to need:

• Mazda OEM ATF fluid or an equivalent (e.g., AISIN ATFMFZ, Amsoil for extended temperature range).
• 8mm hex wrench for the drain plug.
• Funnel for refilling.
• Container to measure drained fluid.
• New crush washer for the drain plug.
• Basic tools for removing the airbox (socket wrench, clamps, etc.).

Set up your workspace on a flat, level surface. If you need to lift the car, ensure all four wheels are evenly raised using jack stands or ramps. This is crucial for accurate fluid measurements and a safe working environment.

2: Draining the Fluid

Locate the transmission drain plug on the pan. Use the 8mm hex wrench to loosen and remove it carefully. Allow the fluid to drain completely into your container.

Once drained, measure the amount of fluid. Typically, for a drain-and-fill without dropping the pan, you’ll collect around 3.5–4 quarts.

This measurement is critical as it will guide you during the refilling process. Replace the crush washer on the drain plug, then securely tighten it to prevent leaks.

3 : Removing the Airbox

To access the dipstick, you’ll need to remove the airbox. Begin by loosening the clamp on the airbox hose and disconnecting it. Next, unclip the metal clips securing the airbox top and set it aside. Then, remove the two bolts holding the inlet path near the front bumper.

Once the bolts are out, the airbox will still be held in place by three rubber grommet mounts. Gently pull upwards to release the airbox from these mounts. This step might feel tricky, but a firm pull will free the airbox. Watch the Video below:

4: Refilling the Fluid

Insert a funnel into the dipstick tube, which also serves as the fill hole. Slowly pour in the same amount of fluid you drained earlier. Using the exact measurement ensures accuracy, especially if you don’t have tools to monitor the transmission temperature.

Mazda recommends OEM ATF fluid, but AISIN ATFMFZ is a popular alternative due to its cost-effectiveness and reliability. Avoid overfilling, as it can cause transmission issues.

5: Reinstalling the Airbox

Once refilling is complete, it’s time to reinstall the airbox. Start by placing it back into its rubber grommet mounts. Reattach the inlet path and secure it with the bolts.

Next, reconnect the airbox hose and tighten the clamp to ensure a secure fit. Finally, clip the airbox top back into place. Double-check that everything is securely fastened before moving to the next step.

6: Checking the Fluid Level

Start the engine and let it warm up to bring the transmission to its operating temperature. If you have a scan tool, use it to monitor the transmission temperature, as the dipstick reading is most accurate at the correct temperature.

Check the fluid level using the dipstick and add more fluid if necessary. This step ensures your transmission operates smoothly and without issues.

General Tips to Keep in Mind

Mazda OEM ATF fluid is the best choice for maintaining optimal performance, but alternatives like AISIN ATFMFZ and Amsoil are great for those looking to save costs.

Always measure the drained fluid carefully, especially if you don’t have a scan tool to monitor the transmission temperature. This ensures you refill the correct amount and avoid overfilling.

If you decide to drop the pan and replace the filter, be aware that older Mazda models may have a fiber filter that’s straightforward to replace.

This process will require more fluid than a standard drain-and-fill, so plan accordingly. While Mazda claims the ATF is “lifetime,” changing it every 60,000–100,000 miles is a good practice, particularly if you drive in harsh conditions or tow heavy loads.

Winding Up

Lastly, ensure the car is on a flat, level surface throughout the process. If shifting feels off after the fluid change, you might need to perform a shift pattern relearn or consult a mechanic. These steps, combined with proper preparation, will ensure a successful and smooth transmission fluid change for your Mazda3.