How do you change the headlamps on a 1998 Ford Expedition XLT?
There are clips on the assembly that you have to release, which pull up. The whole light assembly then can be pulled from the front. DO NOT touch the glass portion of the replacement bulb as the oils from your fingers will make the bulb overheat and blow on use. Remove the old bulb, put in the new bulb and replace the assembly (take your time to make sure it lines up straight). Then replace the clips and you're good to go. I know this because I tried to figure it out myself and ended up having a service guy walk me through it so I would know when I had to do it again.
The halogen bulb contains gas under pressure. The bulb may shatter if the gas envelope is scratched or if the bulb is dropped. Handle the bulb carefully. Grasp the bulb only by its base. Avoid touching the glass envelope.
è The headlamp bulb should not be removed from the headlamp until just before a replacement bulb is installed. Removing the bulb for an extended period of time may affect headlamp bulb performance. Contaminants may enter the headlamp where they can settle on the lens and reflector. Never turn on the headlamps with the bulb removed from the headlamp.
Removal & Installation
1. Raise and support the hood.
2. Raise the headlamp retainers by pushing rearward and pulling up.
3. If equipped, rotate the headlamp bulb protective counterclockwise and remove.
4. Disconnect the headlamp bulb electrical connector. Be careful not to break the retainer clip which is made of plastic.
5. Remove the headlamp assembly.
6. Rotate headlamp bulb retainer counterclockwise and remove.
7. Remove the headlamp bulb by pulling it straight out with a gentle up-and-down rocking motion.
Do not touch the glass bulb with your fingers. Oil from your fingers can severely shorten the life of the bulb. If necessary, wipe off any dirt or oil from the bulb with rubbing alcohol before completing installation.
8. Install a new bulb into the headlamp assembly.
9. Install the headlamp bulb retainer and turn it clockwise to engage the retaining tabs.
10. Attach the bulb electrical connector.
11. If equipped, install the headlamp bulb protective cover.
12. Install the headlamp assembly.
è Be sure the headlamp assembly is positioned correctly with the alignment pins inserted into the proper holes and onto the ribs of the reinforcement.
13. Engage the retainers by gently pushing down.
14. Turn the lights on and check the bulb operation.