So if I am not mistaken my E320CDi needs 229.5 spec (no DPF) 229.5 oil from Merc directly is 5w40. At least that’s what MB tell me. Now my question is, why can’t I use 0w40? Surely all this will mean is that there is better protection from cold? Mobil1 0w40 meets 229.5 too. So surely this should be fine? or is it best to simply stick to 5w40 (from Merc) Mobil1 is slightly more expensive, but in this case I am not bothered. I can collect it tomorrow and get it done straight away. Mobil1 - £60/10L MB branded - £39/10L Thanks.