Can't explain how it took all 8 qts., but these published oil capacities have to be an approximation.
Testament to this is the fact that in 2006 BMW revised the fill from 6.2L to 6.5L (6.6 to 6.9 qts.) for the M54 engine.
Engineers just have to take an educated guess on the recommended oil capacity, which is part of the reason why the spread between Min. and Max. is fairly generous.
For those with a dipstick, filling to the Max. line might give a comfortable feeling, but nothing wrong with keeping it at the mid-point. Might even be preferable.
I can't see how a dipstick can be a precise measuring device - even allowing for engine temperature differences.
As for the 8 qts., one explanation could be that it received the wrong dipstick on the assembly line, or subsequently.
Or, that there is something wrong with the dipstick tube that is preventing the stick from seating properly.
I'd start by taking some oil out via the filter housing and monitoring things.
Or sucking some out through the dipstick tube using a turkey baster and some narrow tubing.
Last edited by Supercourse; 05-07-2012 at 08:40 PM.