I can't find XL-18 at any of my dealers. So since my car was bought used with no warranty, I dicided to go the motorkote route, and I must admit it works great. This is also a friction reducer which from all the rading I've done is what XL-18 is. If my car was under warranty i would not have tried such a venture, but to be honest keep in mind anything that happens is on me anyhow!!!! But It works, still not as smooth as my t56 on my last ZO6 but a huge improvement from the clunky hard shifts I was experiancing.