Please correct me, George (or anyone):
It is my understanding that you you should use detergent oil (single-grade or multi-grade) in order to keep "things" in suspension in the oil (so, they can be filtered-out of the oil).
If you engine had/has used non-detergent oil, I think you should remove the oil pan and clean out the "gunk/dirt/grit/etc" at/in the bottom of the pan. Better being safe than being sorry?
