Why not try to charge the battery first and try starting it again, if it doesn't take a charge then it's the battery. Since you had the alternator replaced in '08 it should still be good. One way to check the alternator is to start the engine first, then disconnect the battery, the engine should keep running, if it stops running then the alternator is bad. Or go to Advance auto parts and have them check both alternator and the battery, their testing service is free. Good luck.

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/ / / Mike
BMW X5 Xdrive50i 2015 F15
BMW 325iC 1992 E30
BMW X5 4.4i - sold
BMW 335i X Drive 2010 - sold
BMW Z4 3.0is 2006 - sold
BMW 325is 1993 - sold
BMW 2002 1976 - sold

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