In the past, I never believed guys like Blackmercedes (above post), but now I do. I cannot see a oil level drop on the dipstick of my 99CLK430 after 5000 miles. I only have 37,000 miles on the car. I use Mobil 1 (0w40). I'm sure it uses some oil. Maybe if I went 10,000 miles between changes I would see a drop? I sometimes think; will this engine not last long because it doesn't use any oil? Then I forget about it.