A) Are the two clones of another? B) At K-Mart last week I bought the Exxon to top of the Mobil 1 in the parents car. Incidentally the Exxon was cheaper by .20$ I reasoned they could be the same thing by the Exxon-Mobil conglamerate. C)It was interesting that a couple weeks ago Mobil Drive Clean said "Synthetic Blend." The Bottle of Mobil no longer says that. Any ideas on what happened?