Porsche, BMW and Mercedes Benz make use of an internal timing chain. ... The down side of the external timing belt is the fact that like all belts, it is a wear item and must be replaced. On average, timing belts should be replaced every 80,000 miles or every 5 years.
How long does a Mercedes timing chain last?
When does a timing chain need to be replaced? The timing chain normally needs to be replaced between 80,000 and 120,000 miles unless there is a specific problem. Issues with the chain are common in higher mileage vehicles.Nov 14, 2019