I've not had my S4 long but not long after buying it I got a minor cam chain rattle so after a few questions on here I decided the best option is to change the oil and oil filter. So I have been and purchased my oil and oil filter from audi (about £100) and with about 8500 miles to go for the next long life service and instead of doing it myself would it be easier to ask audi to do an inspection service which seeing as I am providing the oil and oil filter should not cost that much? When explaining my mileage to the next service to the parts dept bloke he suggested 0w 40 oil which COULD bring on my service light or I could have the 0w 30 long life oil which wont! so I obviously chose the 0w 30. But why would he offer the wrong oil in the first place?