This is really odd. My wife and I just got back from northern WI and the car spent the nights outside (no space in her parents' garages). Christmas morning it was a record low for the day of -26F and the car had no problems with the temp. There were a few nights I worried about the anti-freeze freezing up since in the manual it lists it as good to -31F. This was the car's first brutal winter (it now has almost 12000mi). The only problem we had was the windshield washer fluid kept freezing, until I finally flushed it and put -30F purple stuff with a Prestone booster to -50F.

Before we left NC I had recently changed the oil... I've been using Valvoline SynPower 5w-30. I plan on using 5w-30 in the winter and 10w-30 in the summer.

The car started up smoothly all the time up there. The only thing I did notice is that it took a split second longer to start (probably due to the battery being so cold). And on the nights where it was below -15 the doors wouldn't open all the way... the grease in them turned to glue and wouldn't let the guides all the way out.

-A