my 2003 X5 6 cyl 3.0 is using about 1 quart per 1500 miles. It has 108,000 on it. The 1988 735i that I sold to buy this in January didn't use a quart of oil between 5000 miles changes and it had 265,000. I hope it isn't the oil separator. All of my drives are longer than the engine warm up cycle and I live in a moderately cold climate in Western NC. I do not see smoke, except a little puff of light grey at initial ignition sometimes. No leaks at all. Any ideas?