Quote Originally Posted by Jon K
Yep, any thinner than 10w50 or so and I have a little noise that is not only audible but sometimes shows up as false knock.

10w50 or 15w50 is all my engine sees now.

What weirds me out is that I ran 5w40 for the previous 5000 km with no issues. Any ideas as to why it's suddenly a problem?