thanks, vanos gets the most oil carbon so noticed it there and under it most. Only 2,500 miles, they recommend change 4-5k miles. then every 5k after that approx. I am doing for oil consumption and has helped go from 1 quart every 800 miles to half a quart at 2500 miles. Oil rings get carbon build up.
Since 25,000 miles when I got it in 2004, I had used Mobil 1 for first 150k miles, then they came out with high mileage, last 70k on Pennzoil Platinum high mileage. Now Valvoline Restore and Protect. Will keep changing. Changed every 13-14k miles. won't every do that again.6-7k from n0w on on non turbo engines. 5k on turbo.

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Kevin
2001 X5 3.0i
Phoenix, AZ