Only had the X for a few weeks. On the day I purchased it the battery died and the previous owner replaced it before we could test drive it. Everything was fine then but a few days later I kept getting an intermittent battery light. It would come on and go off after a quick restart and would not return until like later in the night or the next day. Tested the voltage and the alternator was only charging around 12.2volts, not enough to sustain life for the big 4.8 and all the electronics. Swapped out the alternator and I had a huge improvement in the overall drivability of the X. Used to get some hard shifts and random warning lights but that's all a things of the past now. Shifts are smooth and power is definitely greater with the new alternator. I'm even happier now with my purchase.

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2006 X5 4.8is LeMans Blue Metallic (His)
2013 Infiniti JX35 Black (Hers)
(Sold) 2007 X3 3.0si Monaco Blue Metallic (Hers)