| Thanks for replies. It is 2000 540i sport package. only has 33K miles.
I bought it from a reputable dealer. I have not changed
the oil yet but I am assuming that it has the synthetic oil.
I am glad that I also bought extended warranty so I am not
worried about the repair costs. I just want to take good care of it and
keep it for along time. because it is a best looking beemer ever.
I dont really like new body style. And I dont want some small problem to
grow into big one.
To be more clear about the noise:
it's knocking like a diesel engine. I could not even notice it, untill
friend of mine told me about it.
It is still fast as hell though.
no performance degradation of any kind. | 
