Just a quick list of oil additives that have been sued by the Federal Trade Commission for false claims:
http://www.ftc.gov/opa/1999/05/duralub2.shtm
http://www.ftc.gov/opa/1999/09/prolong.shtm
http://www.ftc.gov/opa/1995/12/stp.shtm
http://www3.ftc.gov/opa/1996/07/slick.shtm
http://www.ftc.gov/opa/2001/02/zmax1.shtm
Maybe that haven’t got around to Tufoil yet. Sounds like Slick50. I believe DuPont stopped Slick50 from buying PTFE (Teflon). Same stuff that Tufoil claims is their benefit. Just my 2 cents!
What a shame to see Shelby selling out on Zmax snake oil.
Regular oil changes is your best protection.