How to Change Automatic Transmission Fluid and Filter (COMPLETE Guide)

Introduction

In this tutorial, you'll learn how to change the automatic transmission fluid and filter in your vehicle, a crucial maintenance task that can enhance the performance and longevity of your transmission. Whether you drive a Mazda, Ford, or another brand, this step-by-step guide will equip you with the knowledge needed to perform this task safely and effectively.

Step 1: Prepare the Vehicle

• Lift the Vehicle: Use ramps or jack stands to elevate your vehicle. Ensure the wheels are chocked for safety.
• Position a Tarp and Catch Can: Lay down a tarp or cardboard under the vehicle and place a catch can for draining the fluid.
• Locate the Transmission Pan: Identify the transmission pan, usually found near the oil pan and catalytic converter.

Step 2: Drain the Transmission Fluid

• Remove the Rear Bolts: Loosen and remove the rear bolts of the transmission pan, leaving the front bolts in place to create a controlled leak.
• Use Tinfoil: To prevent spills, place a piece of tinfoil under the pan to funnel the fluid into the catch can.
• Remove Remaining Bolts: Gradually loosen and remove the remaining bolts, supporting the pan as you do so.
• Lower the Pan: Carefully lower the pan and allow the remaining fluid to drain completely.

Step 3: Replace the Transmission Filter

• Remove the Old Filter: Find and remove the bolt securing the filter (usually 10mm) and pull the filter out.
• Check Valve Body Bolts: Snug all bolts holding the valve body to the transmission to ensure proper pressure and crisp shifting. Torque to 8 foot-pounds.
• Install the New Filter: Compare the old and new filters to ensure they match. Lubricate the O-rings with transmission fluid and install the new filter, securing it with the bolt.

Step 4: Clean the Transmission Pan and Install New Gasket

• Remove Old Gasket: Use a plastic scraper to gently remove the old gasket from the pan. Avoid metal scrapers to prevent gouging.
• Check for Metal Filings: Inspect the magnet inside the pan for metal filings, which indicates normal wear.
• Clean the Pan: Spray brake cleaner on the pan and wipe it down with a towel.
• Prepare the New Gasket: Apply silicone paste along the edge of the pan to hold the gasket in place, then align and install the new gasket.
• Install the Transmission Pan: Line up the pan and hand tighten the bolts to secure it without compressing the gasket too much.

Step 5: Torque the Bolts and Add New Fluid

• Torque the Bolts: Using a crisscross pattern, torque the bolts to 10-15 foot-pounds for even compression of the gasket.
• Fill the Transmission Fluid: Determine how much fluid you drained (e.g., if you drained 3.5 quarts, add the same amount back). Use a funnel to fill through the dipstick hole or fill bolt.
• Check Fluid Level: Start the vehicle, allow it to run for a few minutes, then check the fluid level while the vehicle is idle and warm. Add more fluid if necessary.

Conclusion

Changing your automatic transmission fluid and filter is a straightforward process that can prevent costly transmission damage. Remember to regularly check your fluid condition and replace it as needed according to your vehicle's manual. With the new fluid and filter in place, your transmission will run smoother and more efficiently, extending its lifespan. If you found this guide helpful, consider subscribing for more automotive tutorials.