What happens is that the seal where the bulb socket fits into the back of the housing can let moisture get into the lights.
What happens is that the bulb heats up and the air in the reflector/lens housing expands and some of the air leaks out. When you shut the lights off, the air in the housing cools it creates a slight vacuum that sucks in air an moisture from the humid air.
A little bit of condensation is not a real issue since as soon as the lights are turned on, the heat will tend to dry it up. But if it is not humid outside and the condensation continues to build up, you need to remove the headlight housing, drain out any water inside and use a hair dryer to blow inside to dry up the condensation.
Some people will reseal he edges ofthe lens cover with silicon sealant since it's possible that there may be a small crack or break in the factory seal.
I had a similar problem with my 1997 Grand Prix. They really had a problem with condensation, and the heat can build up, and the moisture can cause the lens cover to blow off....That's what happend on my GP. I don't think that is an issue on the Sport Trac because the lens covers are flat and the plastic is thinner with more flex.
I have also heard of some people who swear that you can drill a very small hole in thebottom of the headlight housing and that will allow condensation and any pressure build up to escape...but the hole also makes it easier for condensation to get into the headlight housing?
I would recommend just drying it out with a hair dryer and seal the edges. If that does not work, only then would I resort to drilling a hole in the bottom of the housing to let the water drain out.
...Rich
ostwhore:
