Park the vehicle on a level surface and put on the parking brake.
Place your foot on the brake (parking brake should still be engaged) and start the engine.
Move gearshift through all the gears, allowing time for each gear to engage.
Place gearshift in park, and leave the engine running.
Remove the dipstick from the transmission filler tube. Refer to the "Identifying Components in the Engine Compartment" section in the "Maintenance and Specifications" chapter of your Expedition's owner's guide to locate the dipstick.
Wipe the dipstick clean using a clean, dry, lint-free rag.
Replace the dipstick back in the filler tube, and push it in completely.
Remove the dipstick again, and read the fluid level. The fluid level should be in the designated area marked "hot" on the dipstick if the vehicle is at normal operating temperature. If the vehicle is not at normal operating temperature, the fluid level should read in the area marked "ambient." If the fluid level is low (indicated by the "add" area of the dipstick), do not drive the vehicle.
Refer to the "Lubricant Specifications" section of the "Maintenance and Specification" chapter of your owner's guide to determine the correct type of fluid to add to the transmission. The correct type of fluid may also be indicated on the vehicle's dipstick.
Add fluid in 1-cup increments through the filler tube, using the measuring cup and funnel, until the fluid level is correct.