New. Rebuilt will use china voltage regulator the only part that typically fails.

Also I usually get mine from local store like O'Reilly that have national chain so I have a solid chance of an in stock swap if it fails.

Last X5 Alternator I replaced was only like $30 different new vs. reman.

Also: it's almost always just the VR that fails look into VR swap. Ihave the same motor but not sure which brand and if there is a VR repair kit like the M54 which for $20 returns it to like new status.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)