Like Tiny said I think The multi-vis oil is the easy way to go, although I've used a 20w-40 in motors during the hot season because of 10w- being so light in the hot season for an old motor.
It also has become an issue of what you can buy as a lot of the older types of oil are getting harder to find easily.
With newer engines requiring 5w-20, 5w-30, it is becoming more difficult to find the older weights of oil.
Dan
