A BMW 2 litre diesel for oil change. Took out the oil filter and the paper element was totally clogged up and surprising oil got through it. Checked its history through the service socket and last oil change was 40,000 miles and 4 years ago.
Very lucky as normally the turbo fails using bad oil or the timing chain snaps.
These cars have 24,000 mile change with long life oil but this one showed up a problem that the filter does not fair well. Still ran very quiet and no rattles though.