So my new c63 coupe has 3400km on it. I've now had it parked for serval months do to the winter but I start it every 30days. Last weekend I decided to check my oil for ****s and giggles. Most confusing dipstick and the book didn't help. I took a photo and went to the dealership. They told me to add 1liter of oil and too take the reading from the top two smaller red points. In the book it says that under heavy driving it's likely to go threw .8L every 1000km. Im curious if I have damage my engine. Let me say I do not baby this car. I get about 300km to a tank in other words. The car takes 8.5L so ive been running on 7.5L for probaly sense 2200km. I say this because i babyed it too 2200km For break in period. To what I know you need every drop of oil when you red line. Can anyone give me there two sense????

Your car is completely fine.

I'm not a Merc mechanic , but I'd have to agree that being down about a litre on an engine this size shouldn't do any damage unless you're running the engine at full load for a long time ( ie. constant redline). I've worked/work on CAT and DETROIT engines and usually try to run them a little below the full line. Easier on seals.
On a side note; when I took delivery of my 63 coupe I spoke to the dealer about the oil burning issue with these cars and he told me to swing by anytime I notice the oil is a little low and they'll just top it up ( between scheduled oil changes and maintenance)

These motors burn oil when new. Mine used 1/2 quart every 1k miles. Now at 24k and it doesnt burn any oil.

+1. I burned a bunch of oil when new, now it's fine.

Same as with aircraft engines. You know break-in is complete when they stop burning oil.
Until the rings seat, oil can get past the rings and burn off in combustion. Once the rings seat and settle in, oil can't get past them as easily.

My car didn't burn any oil. Oil light has never come on. 5700 miles just did service A.

^ you check the oil yourself? All these motors burn oil. Yours could have been a bit overfilled when you got it and you might not have driven hard enough to burn down and trigger a light.

this engine is sensitive with overfilling too. my car stopped burning oil at 5000 miles.

Always check oil when warm. You don't want to over fill it.

You're probably right. I do check my oul, but only once every few months. Plus, it has had two oil changes already.