but that raises another issue, what if the fluid was overfilled in the first place.

IMO - its best to follow the manual to check the level - for me I set it on the cold marking which for me with my E300D is 11mm below the 30 mark on stick. On the 722.6 I fill till the lower of the 25C mark on the dipstick and go for a drive.

Once nice n hot I check the level and its at the hot marks.

for faster drain out of ATF I make sure the transmission is at driving temperature, it thins out the ATF and it drains a lot quicker and I usually get more out of the gearbox that way.

Another piece of advice I read from a hydraulics book was to let the filter media soak in the oil for at least 15 or 30 minutes before use, The old MB transmissions use an actual filter media rather than a strainer, I button up the pan, fill it up with 3 or 4 quarts and take a tea break. I dont do that with my 722.6 as it has a foam type media as a strainer and not a true filter.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

If it was overfilled in the first place you'd already have other issues on your hands, most likely.

Of course, still verify using the proper fill level check technique but refilling with the exact amount drained will remove the vast majority of any potential for an incorrect refill.

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

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