Hey everyone!

As i've been reading around, these M156 engines seem very bulletproof. Especially in the later year M204 models.

This thread is more for people to share their experience first hand, with the C63 AMG coming down in price and more new owner opportunities open therefor high millage cars getting into the hands of people who might not have much knowledge of these cars.

Headbolts have been addressed enough to the point where i feel like its no longer necessary to dive into.

There seems to be a few main points of these cars that will one day, undoubtedly need to be addressed and fixed or replaced. Especially with higher millage cars coming downstream.

Camshaft/lifter wear.
Intake manifold leaks/gunking. Leading to harsh hunting idle/misfires.
Camshaft phaser failures.
Rear PCV hose cracking and leaking unmetered air into the airstream.

Let's put the basis at 100k miles or 170k +/- KM's

At this millage range, and anyone pulled a valve cover or intake manifold and checked out in the parts to see how they were doing?
Or has anyone had a failure of said part above, if so. Please list millage of failure, and weight of oil used.

As i've read, on camshaft and lifter wear. The primary reason for this is caused by the intake car being positioned higher on the cylinder head leading to harsh cold starts on the valve train until oil reaches the lifters and camshaft.

A big point i seemed confused be is the PCV on these cars, with the intake manifold being made or primarily composite; why are more people not running catch cans? It seems like the stock PCV valve does a great job at preventing crankcase pressure but maybe in access as oil consumption is a common problem with these cars leading to oil being pooled into the intake manifold and leading to the intake manifold degrading over time.

As people continue to run 5W30 and 0W40 would it be safe to say people should we switching to a thicker oil as millage goes up for better protection as the lifters and camshafts do wear over time.

Another question I have, during a PPI can the cam lobes be seen with a flex camera inserted though the valve cover via the oil cap?

In your opinion at what millage should these items be serviced for long term reliability?

 

You should fix your first line, I think you meant M156 engine (as M157 is the old 5.5 TT engine) and for model I assume you mean W204.

 

Done, thank you!

 

 

I don't want to start an oil discussion here, but it's been suggested in the past 10W60 (depending on the climate) is ideal to reduce the camshaft wear. I'm in Florida and the climate hear would work with 10W60 but I haven't tried it myself.