I grew up in northern Pa.(where the Quaker State oil refinery is) and worked in the oil fields there during the '70's and into the early '80's. Nobody that I knew would think of using Quaker State oil because of the extra high paraffin content in their motor oil. It was the paraffin build-up that caused the excessive gunk accumulation that the oil was infamous for. I dont know if this is still true today but back then it was gospel.
