I'm (was) running Brad Penn 20/50, until it all got squirted out. It's amazing how much oil, in such a short time, can come out of that compromised seal.
It was a shop dinner with coworkers, so we were drinking some beer and having a good ol time for about 3 hours.
So, I think I'm going to run a lighter oil for the winter months. Our winters aren't that bad, so if the roads are dry, I'm driving.
My oil system has a remote cooler. Maybe I need an oil thermostat that takes the cooler out of the loop during cold times.