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For 1990-2009 cars only

When to Check and Change Automatic Transmission Fluid

A good time to check your automatic transmission fluid level is when the engine oil is changed.

Change the fluid and filter at the intervals listed in Additional Required Services , and be sure to use the transmission fluid listed in Recommended Fluids and Lubricants .

How to Check Automatic Transmission Fluid

Because this operation can be a little difficult, you may choose to have this done at the dealership service department.

If you do it yourself, be sure to follow all the instructions here, or you could get a false reading on the dipstick.

Notice: Too much or too little fluid can damage your transmission. Too much can mean that some of the fluid could come out and fall on hot engine parts or exhaust system parts, starting a fire. Too little fluid could cause the transmission to overheat. Be sure to get an accurate reading if you check your transmission fluid.

Wait at least 30 minutes before checking the transmission fluid level if you have been driving in the following conditions:

    • When outside temperatures are above 90°F (32°C).
    • At high speed for quite a while.
    • In heavy traffic -- especially in hot weather.

To get the right reading, the fluid should be at normal operating temperature, which is 180°F to 200°F (82°C to 93°C).

Get the vehicle warmed up by driving about 15 miles (24 km) when outside temperatures are above 50°F (10°C). If it is colder than 50°F (10°C), drive the vehicle in DRIVE (D) until the engine temperature gage moves and then remains steady for 10 minutes.

A cold fluid check can be made after the vehicle has been sitting for eight hours or more with the engine off, but this is used only as a reference. Let the engine run at idle for five minutes if outside temperatures are 50°F (10°C) or more. If it is colder than 50°F (10°C), you may have to idle the engine longer. Should the fluid level be low during this cold check, you must check the fluid hot before adding fluid. Checking the fluid hot will give you a more accurate reading of the fluid level.

Checking the Fluid Level

Prepare your vehicle as follows:

  1. Park your vehicle on a level place. Keep the engine running.
  2. With the parking brake applied, place the shift lever in PARK (P).
  3. With your foot on the brake pedal, move the shift lever through each gear range, pausing for about three seconds in each range. Then, position the shift lever in PARK (P).
  4. Let the engine run at idle for three minutes or more.

Then, without shutting off the engine, follow these steps:

The automatic transmission dipstick is located at the rear of the engine compartment, on the passenger's side of the vehicle. See Engine Compartment Overview for more information on location.

  1. Unclip the handle and remove the dipstick; wipe it clean with a clean rag or paper towel and re-insert it fully. Remove it again and read the fluid level.
  2. Check both sides of the dipstick, and read the lower level. The fluid level must be in the COLD area for a cold check or in the cross-hatched HOT area for a hot check.
  3. If the fluid level is in the acceptable range, push the dipstick back in all the way.
  4. Remember to always replace the dipstick and lock the handle down.

How to Add Automatic Transmission Fluid

Refer to the Maintenance Schedule to determine what kind of transmission fluid to use. See Recommended Fluids and Lubricants .

Add fluid only after checking the transmission fluid while it is hot. A cold check is used only as a reference. If the fluid level is low, add only enough of the proper fluid to bring the level up to the HOT area for a hot check. The level should never read over the HOT mark, so be careful not to add too much. It does not take much fluid, generally less than 0.6 pints (0.3 L). Do not overfill.

Notice: Use of the incorrect automatic transmission fluid may damage the vehicle, and the damages may not be covered by the vehicle's warranty. Always use the automatic transmission fluid listed in Recommended Fluids and Lubricants .

    • After adding fluid, recheck the fluid level as described under "How to Check Automatic Transmission Fluid," earlier in this section.
    • When the correct fluid level is obtained, push the dipstick back in all the way.
        Remember to always replace the dipstick and lock the handle down.
    • If fluid has to be added often, there may be a problem or leak and you should see your dealer.