Hi Bailey, my Haynes manual says 4.5 litres. I'm about to service mine too (same model). What grade oil are you going to use & what else will you do on the service?
Ill be using mobil 1 oil, not sure on the grade, its top notch stuff though. I work for BMW you see and we use it all on of our diesel models when servicing. Mines done 118k now, im having a new cambelt and tensioner, oil and filter, air filter, pollen filter and fuel filter. All genuine parts. Thanks for letting me know mate, much appreciated
