I bought a second hand 1999 Focus estate (1.6) and for the first year I never topped up the oil level once: engine had done about 40K and I do about 6K per year.
Ever since I have had to regularly top up the oil. Every couple of thousand miles the level goes down to lower than half way between the max and min levels on the dipstick and the vehicle needs about half a litre more oil.
Why would the oil consumption suddenly rise and is this a normal level of consumption? No evidence of any leaks etc. Any ideas?