I have a 1992 f250 diesel. This moring I noticed that the windshield looked like it had some oil or something on it. I thaought it was from outside. But when I touched it was from inside. It looks like it is some kind of defroster discharge. THere is no coolant loss visible. And it doesn<t smell like coolant or anything. What could it be? It doesn<t seem to get any worst. I noticed this probably a month ago.

thanx, merry xmas

 

I would guess a heater core leaking. If it has just started then you probably wouldn't notice a huge coolant loss. Does it smell kind of sweet? It is probably engine coolant. If your core is leaking then the defroster will blow it onto the window. You windows will also fog up too. Good luck!

-Matt