Does anyone have any experience, or know if I could safely use Mobil 1 10W-30 during the winter months in my 2000 Odyssey. The owners manual says that 5W-30 is preffered for all temperatures, but 10W-30 can be used for temperatures above 20 deg F. (-7 deg C). The temperatures here in Bowmanville Ontario can sometimes dip to -15 deg F.(-23 deg C). Are these Honda recommendations based on non-synthetic oil?, which mean the synthetic will work ok? A number of people here have said that 10W-30 will protect an engine better than 5W-30. I would like to give it a try unless anyone knows for sure that it does not. One more item: Honda is now recommending 5W-20 oil for its new vehicles, and is saying its also good for 1998 and newer ones as well. Does this fact suggest that the tolerances in Honda engines are too tight for 10W-30?