Hello everyone. I make sacrificial anodes for a living. Anodes are used in a variety of applications. Much of the information shared in this thread is incorrect. However, as someone who has designed, installed, and understands anodes, as well as a fellow car enthusiast, I can tell you that you can't use anodes to protect your cars. Anodes rely on a consistent electrolyte to function correctly. The corrosive environment on a car doesn't offer that.