I have a 1999 E320 with 101K miles on it that I recently purchased from an auction. I do not know the vehicle history, but the sticker from the last oil change said Kendal synthetic blend. That is all I know.

The MB dealer says they use only Mobil 1 full synthetic 0-40 oil for all their oil changes, even my car. They reiterated to never use regular oil, only synthetic.

I have read here that switching to Mobile 1 can cause leaks and excessive oil consumption because of the additives, if Mobile 1 has not been used every time. It seems mine has used other brands and currently does not leak or burn oil.

I have read here that MB recommends extracting the old oil through the dip stick, but the dealer told me they always drain oil through the oil pan plug. Who is correct?

Now I'm confused about oil brand, viscosity, and oil removal. Please enlighten me.