What kind of oil does a mercedes c300 use?

The kind of oil the mercedes c300 uses iS5w-40. Your oil needs to be replaced eventually. Every 5,000 to 10,000 miles is a good rule of thumb. If You don't replace it, there will be issues with the engine. Having high quality oil is key for the engine to run smoothly. You will run into problems with the oil at some point. Bad oil can cause the engine to fail. A normal problem is a nasty burning smell. This needs to be looked into as soon as possible or the car might explode. You could experience terrible gas mileage. Knocking noise may come about from the engine.