Maintenance and Fluid Information for 2012 BMW X3 3.0L
The service listing gives an oil quantity of 6.9 quarts with filter. Use that figure to plan the job, but check the level after filling rather than adding the entire amount without verifying it.
How many quarts of oil does my 2012 BMW X3 3.0L take with a filter change?
With the oil filter changed, the listed engine-oil capacity is 6.9 quarts with filter.
Which oil filter is listed for my 2012 BMW X3 3.0L, and what is the filter number?
The oil-filter part numbers listed for this vehicle include EA15K54-EA, HU816x-EA.

