In order to establish the proper level in the case of both my Jeeps the engine must be running, idling in park. That's the short version. I wouldn't rely on the cold level and checking it after it sat overnight with my vehicles.
Originally Posted by StevieC
Yeah lots of folks are just scoring their engine oil dipsticks and using that. They just make a note of where it is cold when it has been sitting overnight and use the ambient air temperature that day and do it that way.
Originally Posted by demarpaint
The Dorman stick works well. However there are a lot of DYI ways of checking the level on the Chrysler transmissions that came w/o a dipstick. I've seen makeshift dipsticks made with long zip ties. All it has to do is bottom out in the transmission pan and have 5mm markings from the lowest part of the zip tie up about 70 mm. There are articles on the web on how to measure the temperature of the ATF and the chart for the level. A PITA for sure but not that bad to service once you understand how it is done.