Saw a few reports recently from people with NON-oil burning Theta II's who ran Quaker State Ultimate Protection or Quaker State Ultimate Durability (one switched to Euro oils but had a lot of miles on Quaker State Ultimate Durability). Keeping one of those Theta engines from burning is about the best endorsement I can think of for an oil.Quaker State Ultimate Protection is amazing and the biggest steal in quality for everyday price going