I have an '04 F150 I bought used two years ago with 6,500 miles. Since then I sometimes have a problem with a "misting" on the inside of my windshield when I leave it parked overnight. It seems to happen when the humidity is high and the outside temp. dips into the 30's. It is only on the windshield. My coolant level is normal, no smell of anti-freeze, no signs or smell of water damage, heat/air work fine. I had it at the dealer and they found nothing wrong, but suggested that I place my ventillation control **** in the off position when I park overnight. This did little, if any, differance. Has anyone else expierienced this?

 

Sounds pretty normal. It's just moisture from the plenum condensing on the cooler glass.

I'd make certain the condansate drain is clear, otherwise, just turn on your defroster when you start up.

Steve