Hi. Just bought a 98 Passport. How can I check/fill the auto trans fluid? The manual says Dexron III but to have a dealer do it. Thanks in advance.

I am not to sure why you would have to have a dealer check it? I know my husband has checked our himself but that was a different make of car.

In most cases, automatic transmissions must be checked when the engine is running and only after it is warmed up. Driving the car 10 miles or more is the best way to properly warm it up.
Checking the ATF Overview:

* Park the car on a level surface.
* Leave your foot on the brake, keep the parking brake on, and let the engine idle.
* Move the gear shift through each gear. This will ensure that the hydraulic chambers in the transmission are filled with oil. Also, checking the level with the engine running allows for fluid to be circulating normally. By not following this step, you will get an incorrect reading.
* Note: Sometimes, checking your fluid with the car in park or neutral is required. Consult the owner’s manual for more information, or some vehicles have the instructions on the dipstick.
* Locate the transmission dipstick, usually placed at the rear of the engine. Pull the dipstick out and wipe it clean with a paper towel or a rag. Be sure to note the markings on the end of the stick that indicate fluid levels: "FULL" and "ADD 1 PINT".
* Also check the fluid for black deposits, metal particles and dirt. Do this by wiping the dipstick with clean a white paper towel and examining the fluid on the paper.
* Also check that the fluid is clean and transparent, not black and/or having a burnt smell.

To add transmission fluid:

* Only add transmission fluid if it is at or below the “Add” mark. Never fill it past the “Full” mark.
* Be sure to only use transmission fluid that is recommended by the manufacturer. Consult the owner’s manual for this information.
* Transmission fluid is usually sold in quarts. Do not add the entire quart at once; add small amounts at a time until you get the correct reading on the dipstick.
* Use a funnel to get the fluid into the small tube that the dipstick came out of.
* Wait for the fluid to settle after adding it.
* After a few minutes, start the vehicle. If it still is not reading the correct level, add more fluid.

Hope this helps.. Good luck.