Hello Volvogemeinde, My Elk (C30, 1.6D) normally needs an engine oil with the following specifications Oil quality: WSS-M2C913-B Viscosity: SAE 5W–30 and for unfavourable conditions Oil quality: ACEA A5/B5 Viscosity: SAE 0W–30 Well, to my question, you can mix the two varieties, e.g. I always carry 1-2L oil with you (as an ex-passat driver a MUST). I would say, the C30 was delivered with the standard oil – is it wrong if I use the other oil (0W-30) as an optional supplement? Thank you in advance for your tips. Romeo