So I have been using MMO at the prescribed dose listed on the bottle. I have only added it to my fuel tank and not to the oil. It has been almost 2K KM since it has been added on this oil and the oil is turning a dark brown colour. Usually my oil stays a light golden colour from the first few hundred KM's on fresh oil right through to the change 10-15K KM later. I'm not worried that it's doing "bad things" to the oil but I wanted to know if it's the MMO causing it or if it's some other anomaly. I don't believe its doing any cleaning because I have run 2 ARX clean/rinse cycles shortly before this and was using a fuel system cleaner additive consecutively for over 75K KM.