I have some Mobil Delvac 1300 15w40 oil I use for my duramax. This oil is new, however I don't have a need for it and am going to switch oil weight. Anyone want this? It's just sitting on my shelf. There is a brand new unopened gallon jug, and an open half used gallon jug. Probably worth $15-20. Give me a pack of high life for it?