Re: Brew for cleaning filthy gas tanks Home › Forum › Ask A Member › Brew for cleaning filthy gas tanks › Re: Brew for cleaning filthy gas tanks gofastgrampsUS Member - 2 YearsReplies: 54Topics: 25 December 4, 2017 at 5:40 am #68241 Castrol no longer makes super clean, the stuff you buy today is not at as good as the original. not even close.