I just got went through everything you listed.... back in February i left my car at the shop for two weeks. oil leak from housing gasket... might as well do preventive maintenance... CCV-PCV system overhaul and upgrade to cold weather kit. All belts, pulleys... M54 been running strong after that. If your X is near or past 100k than go ahead and do everything.
Good Luck. Next time i'm in the greenvile area I want to see that X running.

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2009 BMW E60 LCI 528Xi


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2002 BMW X5 3.0i E53