I'll second trader4 - either do a load test at home or take the battery somewhere that will load test it off the car.

If the battery drain is really staying that low (and not increasing in the middle of the night for some random reason), I think a healthy battery would be fine for several days.

If the battery checks out, then next for me would be the alternator and voltage regulator.

About the drain - if the car has aftermarket electronics - alarm, radio, etc try to disconnect those and see if it helps. They seem to be the most common source of mystery battery drains.

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David.X5
2001 X5 4.4i Sport
SOLD! at 160k miles