On the V6 is is more of the sprocket not being hardened enough. And. . . not taking into account harmonic vibrations that hammer the sprocket. This is a prime case of history repeating it's self, look at the Citroen SM V6 that was a reliable cut down V8 Maserati.

Porsche has problems with balance shafts on " whatever the water cooled 911 is called " They use a sealed ball bearing rather than oil lubed. Yikes.

They also have a problem with cylinder liners splitting on low mile / lightly driven cars. The issue is too high a cylinder pressure from low RPM / large throttle openings required to hit fuel economy and likely emissions targets.


I'd bet the person designing this neglected to account for intake manifold pulsations ( just like the balance shaft ) and was still viewing the world as being made up of friction-less pulleys and ideal gasses. ( think about the ideal gas part for a bit )


Don't know about this. However, if the actual cooler element is failing and not the MB interface, I'd lay blame on the supplier since it is unlikely MB makes their own.

An automatic trans is a hugely complicated system so I give some room there. This especially true of a modern electronic auto trans where shift timing and clutch volume is monitored to keep shifts consistent. Mix in the variability of drivers + wear and it is extremely difficult to get right.

Think about this, if a driver tips the throttle in during a shift in anticipation of the engine slowing down, line pressure must rise to prevent clutch damage. If line pressure rises too rapidly / too high, the shift will be a slide bump leading to customer complaints. ( RE: driver perceives engine slowing down as car is slowing down. )