Drives: Mercedes S600TT, LX470 SuperCharged, QX4, BMW 750IL
Happens to me every 4-5 months. Put oil in and it goes away. I was told to use 0W40. When it says add 1 Liter it usually means your engine is out of oil. I have never had any oil leaks... I think MB engines drink a lot of oil.
Oliverk, actually I was just about to say that. The onboard computer can and sometimes is wrong. You definitely need to manually check the oil as well.
Start the car up and warm it, then turn it off, wait 5 minutes, and check the oil with the dipstick. That's the best way, since the onboard computer can sometimes be a bit off. Also make sure the car is on level ground.
If there are no leaks, the oil lost is just a sacrificial film in the cylinder wall that is pushed out the exhaust pipe with the fumes of the combustion chamber. This loss is a result of the extraordinary lubricating protection given by synthetic oils which manage to penetrate even through the oil ring of the piston. A true benefit which helps extend the life of the engine about 25% by comparison to engines lubed with fossil oils.
So, if there is no trace of leak, leave it alone. However, I agree that the oil should be measured to check how much is needed to fill the system without going over the normal quantity.
To establish a love raport with your car:
DEFENSIVE DRIVING-Never having to say you're sorry.
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