S500 4Matic 2005
Well I have been using Mobil 1 5w-40 from the dealership since I bought the car reason being they told me that Mercedes had made the switch from the 0w-40 to the 5w-40 for our engines through some bulletin. That was back in 2012. I go there today to find out that my regular parts guy "no longer works there" I am guessing, they let him go. Great guy by the way. Anyhow, get my 8 quarts of oil along with the new filter, wish the new guy Good Luck and I leave. Get home, jack the car up let the old oil out, put three quarts of the new oil in and I happen to look at the box. Sh*t it is 0w-40 :frown Now I realize that both oils are fine for our cars and I would probably never be able to tell the difference and so fourth but my OCD keeps doubting. So my question is, should I run the 0-40 for now and then my next oil change go back to the 5-40?? Or go get the same 5-40 I been using all along and change to that right away?? What do the car gurus here suggest??