See also:

Capacities
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For X3 xDrive28i: Oil levelcheck
The concept The oil level is monitored electronically during driving and shown on the Control Display. If the oil level reaches the minimum level, a check control message is displayed. Displayi ...

Adding engine oil
Filler neck Only replenish the maximum oil amount of 1 US quart/liter if the message is displayed in the instrument cluster or the oil level has dropped to just at the lower mark of the dipst ...