I ran into a problem about a month or so ago with my transmission slipping at about 45 MPH. It gradually got worse, wanting to slip at all speeds, after driving a few miles
(warm-up period). It had transmission fluid in it (more than called for when checked
COLD). Man is that dipstick “Way Wrong”. Finally I couldn’t put off doing something about the “slipping”problem because it became really “Bad”. I picked-up a can of TranX (it’s advertised to stop tranny leeks and slipping) and then drove home from the parts store and decided for accuracy purposes to check the level “Hot”…..well the dip-stick was bone dry. So needless to say after adding the TranX and more tranny fluid, almost instantly resolved the slippage issues. So may I suggest “Never ever EVER check the dipstick if the engine is OFF and the tranny is Cold. The cold marks on the dipstick are no good and absolutely not accurate, they will only give you a false sense of security.

 

There, fixed it for you. #1 problem with how you were checking the transmission fluid level is you were checking it with the engine off. You ALWAYS need to have the engine running to check an automatic transmission. With the engine running there is just too much fluid in suspension in a transmission that drains down into the pan when the engine is off. You will never get any kind of consistent reading on the dip stick checking it with the engine off.

You can certainly check the fluid level with everything cold though. That is the reason for the cold and hot lines on the dipstick. The only difference is that of the thermal expansion of the fluid as it warms up. That is a known value and easy to represent on the dipstick unlike the amount of fluid that can make its way down through the transmission internals after the vehicle has been shut off.