I change my oil every 5K miles, and I always use BMW oil & filter, for $80 you'll get a filter and 7 qts of oil. Let me tell you something, my oil is almost pitch black @ 5K miles. I don't care what BMW tells you, 15K miles between oil changes is another way to deposit dirty particles inside your engine, not healthy for the long run. BMW also says their differential & tranny fluids, and coolant are "Lifetime". Any REAL mechanic will laugh at that fact. It's your call pal..!! Or you can also do 7.5K like a lot of folks here!! But don't waste your time and money on just changing the filter.