Yes from 2013,I did a test at home, I took a hot frying pan, put some RP 0/20 in, it caught fire after about 1.5 min. Then I took some dino Napa 10/30, it just smoked like a blown racing engine. I need to redue this experiment and record actual temps,
My particular Honda with a 5sp manual, the engine turns 3000 rpm cruising 80mph, 3500rpm at 90. Now that produces more heat say the 5sp auto model at that same speed cruising under 2500rpm. In the summer where I live, not uncommon for 100 plus outside.
European cars run heavyweight oils for a reason. BMW m cars use 10/60, others are 5/40, 0/40, why? Because they know it offers more protection than a light oil. There's only 1 reason for light oil, gas mileage. I could care less if I lose one or two miles per gallon if I know I will gain far more and protection of the engine
How can Ford Chevy Toyota say use a 0 20 oil in a V8 then go pull heavy loads and that pickup truck and expect that engine to last three four hundred thousand miles running a thin light weight oil.
If you take a car on the race track say the Corvette they recommend 530 for daily use but on the track use 15/50. Because they know the 5/30. Will be stretched Beyond its limits oil temp gets hot and you putting extreme stress on it so if you run a 15/50 1 South oil gets hot it will probably send down somewhere near 30 weight. Why do you think Chevy says go back to a 530 on a non track day? Because they want to continue to achieve their fuel mileage numbers and Cafe.