I have been supplementing a small drip with SAE 10wt non-detergent oil. As California, in they infinite wisdom, banned non-detergent oils, I feel I have no alternative but to switch to an alternative. Mixing oils can bring there set of problems. Yes, I wish I wasn't faced with this issue. I had to remove and clean the oil pan a few months back because of the same Issues. But I do appreciate the information.