Oil Analysis by Blackstone Laboratories. This is used to test the used oil coming from your vehicle, and can give you insight of the health condition of your engine. I can show you a sample report to give you an idea, but this is a great way to keep track of the health of your car over time. I would recommend this service annually. This includes a basic report + TBN report.
To learn more visit: https://www.blackstone-labs.com/