This happend to me couple months ago, heard a noise for about 3 months just thought it was a idler pulley making the bad bearing noise but turns out it was the fan. I had to replace about $400 worth of parts. I didnt replace the fan clutch or fan blades I just left them off completley to test results. my car warms ups in about 7 mins now instead of 15mins the motors seems to run better and the temp gauge is reading just like normal. Temps where I live have been around 45 F. If the car runs the same this summer I will not put a new fna clutch and blade on I think the X runs just the same if not better.
http://www.xoutpost.com/bmw-sav-foru...ndle-cold.html