transmission fluid level

[BENZE220AMG]

Hello again, I am still unable to resolve this issue; nonetheless, how can I determine the appropriate number of ATF required for my gearbox?
If I immerse my dipstick into the tube before to a drain and refill to the same level post-drain, how can one ascertain the accuracy of the measurement?
The dipstick I have ordered is an aftermarket one with increments of 10, 20, 30, 40, etc., however it provides no useful information.

I cannot just pour in 6 or 7 litres and assume that is accurate.
Does the authentic Merc dipstick possess the accurate high/low measurements, or need I consult a dealer for verification?
Any feedback is once again welcomed.

[TechnoTrailblazer]

They possess a predetermined threshold for cold temperatures and a distinct threshold for hot temperatures. The dipstick must be of the appropriate length.

[BENZE220AMG]

Thank you. Assuming it is the appropriate length, I may state that at 80 degrees, it should register between 10 and 12.
I should verify that it is 1220 long, since I recall seeing a measurement in the 900s, despite it being my waggon.

[TechnoTrailblazer]

The temperature influences the oil levels, which fluctuate when the oil cools and warms owing to expansion. Ensure to transition the gear selector through each gear for 20 seconds, commencing and concluding in the park position. A scanner would further provide the temperature of the automatic gearbox fluid.

[BENZE220AMG]

I have confirmed that it measures 1220 mm in length. Indeed.Caused me concern momentarily.

[BENZE220AMG]

Indeed, I should and will likely need a scanner at some point.
For the time being, I will use a temporary gun to target it.

[Needsnewtyres2]

The length of the dipstick is irrelevant; the black triangle at the top of the dipstick's plastic part encounters a limit above the gearbox sump, enabling the black measuring section to indicate the fluid level from above. It is customary for a significant portion of the dipstick to protrude from the dipstick tube in the engine compartment.
The ATF level is assessed while the engine is running, in park, on a flat surface, after a 30-minute drive when heated.

[BENZE220AMG]

Thank you. I was concerned that a shorter measurement may provide inaccurate results, but I appreciate the clarification.
It may take several days for it to reach in New Zealand, at a minimum.