LOL - that's what I had in mind actually, because I always have oil left over from car oil changes, AND I just switched to using Magnatec.
Thanks.
The reason I asked was... I went to a Bunnings information session years ago on how to service your mower. The guy said to some lady there that 4 stroke oil was just the same as car oil. He was hinting if the car oil they used was cheaper than 4 stroke, they could just use the car oil instead. (And the 2 stroke thing.)
Come to think of it, he was talking about synthetic oil - because I remember now he said you could use it as 2 stroke oil, but it would be expensive.