[OSUF15]

I have a lease that's up in a few months and I recently passed the 60k mile mark. In that 60k service I'm told I have to change the spark plugs and diff and transfer case oil. There are other things too—which I can understand are needed. But the transfer and diff fluid oil and spark plugs I'm not sure of. I have even been told that changing these fluids too early can lead to more problems. On my last e70 x535d lease I went 70k miles and was never told these particular fluid changes were required. Are these fluid changes something I can be charged for if I don't do before turning it in or are these "recommended" fluid changes. The car is almost three years old, it's an f15 x5 35d. Don't mind the cost, it's just the timing is unfortunate being at the end of my lease.