KEY08

My manual says 9 for 2010 E 550.
And I would be very nervous about this engine's life after running the oil down to 2.5 Qts

Yidney

Something does not add up here. You said you checked the oil level "after a cold start." What do you mean? You started it then stopped it and let it sit a while? You didn't check it with engine running, right? You should have checked it before you started it. Once you start it, all the oil is splashed around in your engine, and you have to wait a while for it to run back into the pan to get an accurate reading. How long after you shut it off did you check it? Ditto at the auto parts store.

But what is really odd is the notion that you can lose over 6 quarts of oil in a 5-7 miles out your oil cap. I don't believe it. Sure, oil will spit out. Not sure about yours, but under my cap is a section of timing chain where it goes over the cam gears. So that rotation will fling oil. But over 6 quarts? In a span of time where you went from not smoking to smoking in an instant? Do not believe it. Plus, if you were 6.5 quarts low, I assume your car would give you a message far more urgent than check oil at your next fuel stop. So the best case scenario is that the dealer was simply wrong about how much oil was still in there.

Arrie

I have no problem to believe that the timing chain can throw that oil out very quickly. The chain is right under the oil fill cap, which is a very stupid design in my opinion. They could have places the oil fill just a few inches towards the center line of the engine and oil would not be thrown out by the chain if the cap is missing.


But I agree that there should have been messages way more aggressive if the oil really went down to 2.5 qt. And if it really did I would be asking for a new engine.

KEY08

The OP's concern about a slight overfill is nothing compared to this latest revelation in this thread. I wish you well and you will know in pretty short order how your engine has fared over the past several days.

cc16177

I will be contacting MBUSA as well as the dealer who created the issue over the next couple days. I want to relax a bit and go about this in a level headed way rather than immediately after yesterday which was extremely frustrating for me...

I will definitely keep this thread updated as I know more from both parties.

cc16177

To clarify, by "cold start" I just meant:

a) it was 35 degrees out
b) car had been off all night
c) I started it up and immediately checked the dipstick level

As I said earlier, I really don't know much about engines, there's a reason I buy CPO cars now because I rely on other people to do the work and I like knowing it's "guaranteed". I didn't realize I should not check the oil level with the car running.

When I checked it at Autozone, the car was off. That might explain why it was dry the first time and 1/3 min-max the second?

I checked the oil again this morning in the exact same manner as yesterday, "cold start" (or what I consider a cold start as described above) and the oil level showed right at the max.

I don't know if the oil cap being loose would have caused it to be dry yesterday... at this point I am going to wait and see what happens as well as reach out to MBUSA and the dealer to see what they have to offer me.

Yidney

Ok, your point c does not clarify. But my plain reading of that is that you checked your oil level with the engine running. If that is the case, then what you read on the dipstick was meaningless. And I don't mean just somewhat inaccurate, I mean meaningless. Like if your chemistry teacher told you to measure how much liquid was in a beaker, and you measured it while somebody had a lid on it and was shaking it violently.

Edit: Ok, now it See that you did in fact check with the engine running.

threeMBs

Sorry, yes you're correct. Did not pay attention that both you and the OP have 5.5L engine vs. my 4.6L.

thefisch

Next time you check it in the morning, just do it before you start the car. After driving I normally wait 30 minutes if I can before I check the dipstick. But I usually check during the day before it is driven - not that I check that often. Typically only after an oil change and later on if I have any concerns.

Arrie

I check oil level every time I fill up.

thefisch

I used to do that but after years and years of no issues I've slacked off. Now when my wifes car gets an oil change about every 4-5 months, I check mine as well. In between I look out for smoke and what's on the garage floor or in my spot at work.

jahquan3

You guys are the real deal....I never check mines smh.

BenzV12

What a drama, at least your engine didn't get any damage .I check mine before starting the car and every milestone so to speak .

Swoosht04

It sounds like you checked it while the motor was on and the dip stick came out nearly dry (oil was not sitting in the pan but running around the motor doing what it's supposed to). You then drove the car and checked it with the motor off and saw that the level was somewhat normal. If you would have let the car sit longer and on a level surface I bet the level would have been normal. Looks like they (or somebody) did not put your oil cap on tight. It fell off (No Evap/Emissions codes?) oil flung out like crazy (car would have sound weird and possibly ran like crap) and the flung oil and cap on the manifold caused the smoke.

Funkster

As mentioned above, the higher oil level can cause increased oil system pressures and can force the excess oil past seals. I am not very familiar with the Mercedes 550 heads but oil does get pumped up there and drains back to the crankcase. It is engineered for just a certain amount of oil to be in the heads before draining. Excess oil can be forced past valves and covers. Sometimes excess oil is forced past seals without damage causing some people to say "It doesn't matter". But it can cause damage and why take a chance with such a nice engine?

Arrie

You are so wrong. Oil pressure to lubricate the engine parts is generated by the oil pump and it does not matter how much you over fill. The pump makes the pressure it is made to make. Under filling will cause the loss of oil pressure, which is the absolute worst thing to happen to the engine.


Over filling can be harmful as the crank shaft will reach the oil surface and start mixing air in the oil. The oil could (in theory) foam up, which can also lead to the loss of oil pressure but for this to happen the over fill needs to be a lot more than just one quart or so.

beejAMG

i dont understand mate...
didnt you originally ask the question as to why over filling is bad?
now youre answering your own question....

are we getting an "F' after this?

Arrie

That question was for a "know it all" earlier in this forum that spreads out misinformation. He never replied to the question.