Easy steps in changing the transmission fluid and filter
1. Make sure the fluid is warm. Warm up the car so the transmission is at normal operating temperature. Pull the transmission dipstick (located near the firewall in most cars). Fresh fluid is translucent and cherry red. Some darkening is normal, but if it is reddish brown or mustard color and smells like burnt varnish, it is worn out.
2. Drain the fluid by loosening the pan. Select the correct filter replacement based on pan shape and prepare a large pan to catch the fluid. Then loosen each pan bolt a turn or two and loosen one corner more than rest. Drain mostly from this corner.
3. Finish removing the pan and any gasket material from the pan or case. Avoid scratching the metal and make sure the pan�s gasket surface isn�t bent or distorted.
4. Remove the old filter. Most transmission filters are held in place with a bolt or two, but some are held by a clip. Be careful to include O-Rings or other seals.
5. Install a new filter. Use the clips or bolts from the old filter. Be sure O-Rings, etc. are in place. If the filter has a long intake neck, gently push the neck into place without unseating the O-Ring.
6. Clean the pan thoroughly. Inspect the pan before cleaning. A small amount of fine grey clutch dust is normal. However, if you find metal shavings, there has been transmission damage. Clean the pan with solvent and wipe dry so there is no harmful residue.
7. Position gasket on pan. Some gaskets have four holes slightly smaller than the rest to allow four bolts through the pan and through these smaller holes to hold the gasket in place.
8. Hand tighten pan bolts in a criss-cross pattern. After that, use a torque wrench to tighten bolts to proper ft-lbs as per manufacturer.
9. Refill the transmission using only the amount shown as �refill capacity� in the owners manual using the type of fluid specified for the vehicle.
10. If doing only a partial fluid replacement, skip to instruction 12 below. If doing a complete fluid replacement, follow the steps in instruction 11.
11. You now have replaced the fluid in the pan. To replace the fluid in the torque converter and oil cooler also, follow these steps.
Step 1. Obtain the total system capacity of the vehicle from the manufacturer. Have this amount readily available.
Step 2. Disconnect the oil cooler line from the oil cooler. As you may not know which is the pressure side and which is the return side, have both directed so the stream of fluid will be directed toward a receptacle.
Step 3. With another person, be prepared to add ATF to the fill area as it is being pumped out of the oil cooler line.
Step 4. Start the engine, and as the old fluid is pumped out, add fresh fluid to the pan.
Step 5. When either the fluid color brightens or the total capacity has been replaced, shut the engine off and re-attach the oil cooler line. All fluids has now been changed.
12. Recheck the fluid level. With the car on level ground, set the parking brake and the transmission in �Park� or �Neutral.� Let the engine idle for a few minutes. Shift the transmission into different positions before returning the lever to �Park� or �Neutral.� Check the fluid level again and check for leaks.
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