Windchill doesn’t factor on inanimate objects, if the actual temp was 0 that’s as cold as the car got. Windchill might drop the temp to 0 quicker than without it but it wouldn’t ever hit -25Paul, I don't know if you had the same winds we got down here in CT, but with the wind chill it was -25 degrees. That's darned cold. I'm betting you're going to find out that the cold was the factor with the gasket or a fitting contracting.