warranty question

If under warranty, yes they will replace a leaky headlight housing....

My 98 GT : the front window cracked from the seal inward. REPLACED :)

My 04 GT : the rear window cracked from the seal insward. WILL BE REPLACED UNDER WARRANTY AS WELL :D
 
I was just at my dealer yesterday and they have a poster at the service island. It has pictures of several headlights with various stages of condensation even one full of water.

Bottom line, they will replace them under warranty. I'm not sure about the used car warranty. Is there any of the factory warranty left?