My wife got a 2014 Mazda 6. The manual says 0W-20 in the US, 5W-30 if you live anywhere else. This [censored] scares me. I read it as,"If you really want to protect your engine, use 5W-30. If you want to meet CAFE standards at the expense of your engine, use 0W-20.
What would you do?
What would you do?