Some information first:

Hot / Cold is trans fluid temp not engine coolant temp.

If you sit and idle, the engine will get hot way before the trans does.

Oil expands when heated.

The torque converter / front pump / cooler need to be full of oil before the level can be checked. ( Engine running )


So, for a trans that is at the proper fill level: If the trans is cold and engine not running , the level will not be accurate. In all cases the level will be higher than when running even though the fluid has contracted. This extra level comes from the torque converter / cooler / trans lube systems leaking down to the pan. The longer the trans site, the more will drain from the torque converter.

Cold not running checks are more for, " Is there any fluid in there?" and " We don't know the recommended fluid change amount, is there enough in there to start the motor? "

Also be aware, when adding fluid let it drain down the tube otherwise you will get a inaccurate smeared reading. Give it a minute or two, sometimes longer. ( the motor can be off for this but restart for the check. )