Battery charging issues...

[Davidf]

So, my 2008 X5 4.8i was having battery issues. Occasionally and randomly, the battery would die while driving the car. Always started fine, but would sometimes go completely flat while driving to the point that the engine died. Jump the battery, get it home and recharge. All good except when it happened again days or weeks later.

Quick check indicated 12.5 volts static and 14.0 volts with engine running. Seems all good. I did notice that occasionally there was a failed bearing sound coming from the alternator/idler pulley area. Stop engine and restart and the noise went away...curious. So, I decided to replace the alternator (AGM battery tests fine and holds a charge while car is inactive).

Hopefully, the rebuilt (from Autozone) Valeo 230 amp alternator does the trick as I have a 1200 mile road trip coming up soon. Half of which will be pulling an Airstream.

Anyone else have similar symptoms and resolution? BTW, I don't think the issue is from short trips not allowing the battery to recover.