What Is The Best Outboard Motor Oil?

I’ve got a lot of experience when it comes to using different outboard motor oils with boats; I worked in a boat repair shop for quite a while and I’ve had my own boats for a number of decades at this point. Frequently, I get asked a question that, even with all of my experience, I’m not entirely sure how to accurately answer: what is the best outboard motor oil?

I’m not really sure what the best outboard motor oil is. I have experience with Yamaha and Mercury and Evinrude and I definitely believe that those three are among the top brands in the industry, but I’m not certain if I could say that one of those brands is particularly better than the other. It’s a really tough call, as certain brands are better for certain uses than others.