Hi, the transmission will take between 5 - 6 quarts when you remove the pan and replace the filter.
You are probably pretty close but you really need to have the fluid level checked using the Mercedes dipstick tool to be sure that you are at the correct level.
Your Mercedes uses a "lifetime" synthetic fluid but I recommend replacing the fluid and filter every 60,000 miles and at least every 75,000 miles.
Let me know if you have any more questions. I'll be glad to help.
Because it didn't seem to change gears right after the 5 quarts, my husband added another quart for a todal of 6 quarts. While we were driving something popped (sounded like a soda pop can) and then we started smoking. We pulled off the road and checked there was fluid coming out onto the manifold. But, it is a small leak and we were able to drive it home. Can you advise us on what happened? It seems to change gears ok.
I suspect that he added too much fluid and the excess was pushed out the breather on the top of the transmission.
What do we need to do now???
I'd get the fluid level checked tomorrow to be safe.
He put a string (he is a good problem solver) on a weight down the tube on top of the transmission where the oil was put in and he came back with fluid.
That's good but not very accurate at all. You really need the Mercedes tool in order to do an accurate measurement.
Click here for the tool.
Would that have hurt the transmission in any way??? Where can we order the Mercedes tool and how much does it cost???
I don't think it hurt anything but you really need to correct the level before you drive much further. Too much fluid can cause foaming of the fluid and cause internal wear.
Did you see the link for the tool?
Yes, thank you.