So I live on the North East shore of Lake Ontario. Probably in the same climate as folks in the Northern U.S.A. It is fall now and I am sadly getting ready to put the RG away. The previous owner used HD Syn 3 20w50. I have notice 10w50 synthetics from LUCAS and CASTROL at the local Walmart and Canadian Tire. Should folks up North continue with 20w50 or should we use one to these 10w50 options for because of cooler spring and fall?