Just came in from the garage with an outside temp of -35C. Gave a shake to bottles of GC 0W-30 and Mobil 1 5W-30. You could still hear the oil slosh around inside but with a shall I say thick viscosity. Shoke some GTX 5W-30 as well and it was still liquid but thicker than the other two. Forecast to go down to -40C tonight so will get a good test of the cranking ability of all three as we have to get three vehicles underway early tomorrow morning and each of the the three above mentioned oils are in their respective vehicles.