Okay if the E90s dont have dipsticks or anything ....thats just whack!
Besides that fact I would never wait for the full 12000 miles before change.......I change the oil at 7000 miles.....period.....synthetic shmyntetic.......oil is oil and it will burn and I dont care what they say.....I am not comfortable with keeping it there for 12,000 miles

. Now having said that since your warranty covers oil changes I doubt they will agree to do it earlier than that for free. I have a used car and I am more worried about the engine so I change it more regularly. Went to my local dealer yesterday for a oil change and he agreed with me but ofcourse would not be official about it. He showed me a SAAb in his garage that had its engine stalll cause the owner used the factory recommended intervals....not that it will happen to every car...but whats the harm in changing oil at 7000? Its just 50 bucks more. Thats my 0.02 on bimmer oil change policy...

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OH BY THE WAY....welcome to the club.