Originally Posted by Chaddz3
Change it when it gets dirty.... When you can't see through it anymore, its dirty enough that it should be changed.. Or if there are signs of contamination in the oil (water, fuel, etc.)
TboneZX3 summed this up, but I want to add something to it.
My bypass filtration system doesn't let the oil get dirty. The picture below is almost 3,000 miles on the oil. Most cars would already have the oil in the sump begin to darken. Mine looks so clear, you have to get the angle of light correct to tell how high it is on the dipstick.
With that being said, I will have to rely on UOA's to tell me when it's time to change the oil. I guarantee you, it will not be less than 15,000 miles or 18 months. I'm expecting beyond that. I also guarantee that my engine will wear LESS than any 2012 Focus without a bypass filtration system using Ford's recommended lubricant for 10,000 miles or less.