So, big Al, if say I was running NO internal cooler, what then? Then I wouldn't have to worry about the cooler path. I guess I could run whatever viscosity I want depending on ambient temperature and oil pressure then.
Like I do. If I lived in Georgia or Florida, I'd run 20w50 year-round. But up here in the not-quite-so-hot Hudson Valley of NY, I run 10w40. My oil pressures and temps support this.
So for Lisa, the answer to what you end up running depends on where you live and when you drive.
Also, I don't suggest extended warmup times. Thirty seconds or a minute max, then drive off. Just take it easy for the first few miles.