Dip stick shows no oil level on first removal, reinsert it and level is fine. What’s up with that?

When I first got my E350, this really threw me. I remember checking oil the morning after getting the car home from the dealership, and thinking I must have lost a quart just on the drive home. Although I'm now used to the dip stick initially coming out dry, it is a little of an annoyance. It wouldn't be quite as annoying if the braided fuel line wasn't positioned right over the top of the dip stick. Now that is annoying!
 
So every time I first check the oil level in my wife’s Mercedes, when I pull the dip stick it shows zero oil. Absolutely dry dip stick like it is a few quarts low. I reinsert it and count to ten and pull it and it now shows oil, actually sometimes too much oil but it is serviced at the MB dealer and I assume they put in the right stuff and amount. The top of the dip stick where you grab it has a nice “O” ring on the part that goes in the tube. Tight seal at the top.

I’m trying to figure out what causes what I observe and have come to the conclusion that the tube the dip stick rides in goes well into the oil pan and when the car is operating, the oil level is below the tube end. The dip stick does not stick out past the end of the tube. When you shut off the engine, the oil returns to the pan but it can’t come up the dip stick tube because of the tight seal and the other end. Removing the dip stick allows the oil to flow up the tube so a second attempt works. Does this sound right?

Any other cars out there with this peculiar oil level check feature?
Hi.
My OM642 does exactly this.

First time i checked the oil, my heart skipped a beat when i saw zero oil on the dipstick.
 
I read the level on the side the level marks are on the dipstick.

I have never seen a one sided marked dip stick. Oh, well....

In your case, I got a feeling you are smart enough to flip it over and get a pretty good idea by looking at the other side.;)
 
I have never seen a one sided marked dip stick. Oh, well....

In your case, I got a feeling you are smart enough to flip it over and get a pretty good idea by looking at the other side.;)
Every car/truck I've had only has marks on one side of the dipstick. Yeah, I look at both sides, lol.
 
My 2004 Mazda 3 2.0 did that if you pulled it first thing in the morning . It almost gave me a heart attack the first time. I don't know how it's possible for something to be sticking down into a pan full of oil and come out dry, but it happened every time.
Unintelligible molecules?
 
The Mercedes dipstick tube is sealed at the top by a rubber o-ring as others have said. It's just the way a Mercedes is made today.

One side of a dipstick may show a higher marking on any car. The side that is lower (and usually almost straight across) is correct. The high side has scraped against the tube and has picked up splash or run-off is you pulled the stick, wiped it, and reinserted it (dragging one side through what came off the stick when pulling it out.
 
or how about the 2az-fe engine in my scion tC?? When you first change the oil, pour the oil in, check the dipstick.. ZERO registers on the dipstick. Wait.. then wait again.. wait.. all of a sudden more and more appears on the dipstick, this is after the engine was run. Once it's to the full level then magically it's always at that level.. Maybe the oil went through the domain where all the socks from the dryer go when they disappear!! 🤪
Here is why. When you pour the oil in the engine it is probably poured onto the head at room temperature ( oh God, now people will want to preheat their oil before pouring in) The room temperature oil slowly works it’s way downward from the head, downward inside the block, to the oil pan. The dipstick is positioned in the sump of the oil pan and it takes a while to gather and raise the level in the sump. :)
 
Here is why. When you pour the oil in the engine it is probably poured onto the head at room temperature ( oh God, now people will want to preheat their oil before pouring in) The room temperature oil slowly works it’s way downward from the head, downward inside the block, to the oil pan. The dipstick is positioned in the sump of the oil pan and it takes a while to gather and raise the level in the sump. :)

thanks Snagglefoot.. I never thought of that aspect of it.. The changes in temps as the oil moves throughout the system. It's odd as this engine is the only one that seems to show no oil but later on expands, it was alarming when I first got the car but now it just something I got used to. But your idea does make sense.
 
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