One problem related to oil pump has been reported for the 2006 Mercedes Benz R350. The most recently reported issues are listed below.
2006 mercedes R350, check engine light on. Replaced magnets and check engine light returned. Diagnosed as defective balance shaft & gear. Mercedes says motor has to be removed to replace balance shaft, gear, timing chain, oil pump and related tensioners and guides. This is a defect that that mb has been aware of since 2007. Car is sitting in my driveway because driving it risks severe engine damage due to possibly jumping time.