A Mercedes-Benz automobile requires synthetic motor oil rather than natural oils, according to BenzShops.com. The site states that the high level of function and performance of a Mercedes-Benz calls for a highly efficient oil.
Mercedes-Benz offers a list of motor oils that they recommend for use in their cars. For model year 1998 or later, suggested oils include: Mobil 1 Tri-Synthetic 15w-50 and 0w-40; Valvoline Synpower Full Synthetic Motor Oil 5w-40; Castrol Syntec 5w-50 and 10w-40; Quaker State Full Synthetic European Formula 5w-40 and Pennzoil Synthetic European 5w-40. Other options include 76 Pure Synthetic Motor Oil 5w-40; Castrol TXT Softec Plus 5w-30 and Shell Helix Ultra 5w-30 and 5w-40.