It was -37C this morning at the Edmonton Alberta Airport and I had my first opportunity to test the starting ability of my 86 VW Golf running Castrol HM 5W-30. It turned over slowly but still at a reasonable enough pace to fire off after about three revolutions. A slight whirring sound could be heard for a couple of seconds until the oil made its way to the top end of the motor. Conclusion: the HM at 5W-30 is going to be okay for extreme winter use. My 2000 Chev Venture van loaded with ESSO XD3 0W-30 started on the first turn as though it was still summer. That has got to be one heck of a good all-season oil for the north. The 89 Dodge van and 90 Accura that my boys drive also are running Castrol HM 5W-30 this winter and they both fired off first crank with no hesitation. All of our vehicles are equiped with oversized high capacity batteries that are monitored and kept at full charge when cold weather is forecast. This more so than than anything else is the the reason they start unassisted in these extremely cold temperatures. I think we are in for a long cold winter this year.