I would definitely say, that was the issue. We have to ensure that our vehicle's oil level is at the maximum at all times. I'm curious to know why the S63 engine consumes so much oil period. My E63 AMG, would consume about 1 liter of oil between oil changes every six months.
But since owning my X5M, I'm topping off the oil about six times between oil changes.
And it seems the harder I run it, the more the oil fill light will notify me to add another liter of oil. I just purchased a F80 M3, but will be curious to see if it drinks oil like my F85.
