I have a 2013 427 convertible with25,700 miles. I have changed the oil since new every year or 5,000 miles whichever came first. I have always sent a sample of my oil to Blackstone labs for testing. This report I just received looks good with the exception of titanium that shows up at 17ppm and the other five reports showed 0ppm. All of the other categories show similar numbers as the other reports. I have not heard any strange sounds coming from the engine, but this has me worried. The car has not been modified and driven pretty much normally for a Corvette. What are your thoughts?