I, too, bought my 08 550i three months ago. On a return trip from Houston, TX to Miss Gulf Coast I got the low oil message. Of course it startled me. I pulled off the interstate 10 about 5 min later and added 1 quart. Car ran smoother and no more problems. Call bmw service next morning; they advised me that 1 quart consumption every couple thousand miles is, indeed, normal. Guess I'll keep a quart in the trunk, just in case.
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