It says in the manual I have to replace it every 22,500 miles. I’ll be there tomorrow with my 2019 ioniq. What is it, and how do I replace it? I emailed corporate Hyundai, and they didn’t know what it was. Neither did my local Keyes Hyundai dealer. What happens if I don’t ever change it? I drive a lot, by the way. Over 60,000 miles per year.