The following covers Lincoln Navigator models from 1998 through 2000. If you drive your Navigator in severe conditions, change the automatic transmission fluid twice as often as you would if you drove the vehicle under normal conditions.The normal maintenance schedule is every 30,000 miles. Ford recommends Motorcraft Mercon XT-2-QDX or Dexron Mercon III automatic transmission fluid for the Lincoln Navigator.
Drive your Navigator for about 20 minutes to heat the transmission fluid. Raise and support the vehicle with jack stands. Position a large drain pan beneath the transmission. Use a socket wrench to remove all but the four corner retaining bolts on the transmission fluid pan.
Loosen the corner bolts four turns each. Fluid should begin to come out around the seal. If it doesn't, you need to break this seal. Grasp the pan and try to move it or gently tap the pan with a rubber hammer. When the fluid begins to drain from the pan, wait for it to stop. Remove one of the corner bolts. More fluid should drain at that corner. Remove the remaining bolts while carefully draining the rest of the fluid into the drain pan.
Clean the pan and the reusable gasket with a safe solvent and let them air dry. While they are drying, remove the fluid filter and the O ring, if there is one. Install a new filter and O ring, if equipped.
Position the gasket onto the fluid pan and reinstall the pan. Tighten the bolts evenly to 10 ft-lbs with a torque wrench. Take care not to over tighten them.
Measure the amount of transmission fluid that you drained out. Add the same amount of new fluid to the transmission through the dipstick filler tube located beneath the hood of the vehicle. You may need a funnel to pour in the fresh fluid.
Engage the parking brake, block the wheels, start the engine and let it idle. Check the fluid level. If it's correct, replace the dipstick and drive the car for a few minutes. Park the Navigator on level ground, check the fluid level and add more fluid if necessary.
