I have been using Spectro products for over 20 years in every motor that I own; car,boat, motorcycle, watercraft and sled. The only "green" oil that Spectro blends is their 2-cycle oil. Most finished lubes are an amber color, the "green" is nothing more than a dye that the blender will add. The dye is very helpful in premix applications to show that oil is mixed with the fuel. If you are draining you engine oil after "X" hours and it is still "green", don't use it. The oil is not doing it's job of holding contaminates in suspension to allow them to get drained out at the oil change. Ken