Car is 18 months old and has done 14k. I've only had the car a few months and oil is rather black - showing 5%. I suspect the oil has never been changed before. I'm not a fan of "extended" service lives and as I do a lot of short journeys I'm going to do an oil change myself. Went to local dealer and was offered 2 different filters - one was £20 and the other was £40!!! Parts guy didn't know which one I needed but agreed to refund the one not used. Both filters are the same size but the expensive one has a spring on the bottom. Anyone else come across this? Thanks.