The Timing Chain system on the N47 engine is positioned at the rear and away from regular service reach. According to engineers, it is part of the engine that does not need to be serviced because it is believed to last the vehicle’s lifetime. However, this is not the case. The Timing Chain is prone to rattle between 40k and 70k miles; an indication that it could snap at any moment. When the Timing Chain does snap, it can cause catastrophic engine failure. The Pistons immediately lose timing and hit the Valves, causing them to bend and hit the Rocker Arms. All this damage can only be corrected with complete replacement of the Timing Chain system.