I can't see any reason for water to get in the transmission unless it went under water from a flood or crossing a stream. If engine coolant is getting into the transmission I would blame the transmission oil cooler in the radiator in which case the radiator would need replacement and the transmission flushed professionally. If the vehicle was driven with coolant mixed in with the Transmission Fluid you will probably have transmission failure before long.
Heater core leaking?
To loosen:counter-clockwise.
Yes water cause leaking
Try twisting or turning it. If it is frozen because of the cold, get a rag with hot water and hold it over the top of the dipstick. If it is not frozen, then that is not a good indication.
ofcourse
change the fluid after finding where the water comes from water will cause rust in the transmission if left in
Remove the water return line from your 1998 Chevrolet pickup truck water pump. Remove the water pump belt. Remove the water pump retaining bolts. Reverse the process to install the new water pump.
Failed radiator transmission cooler.
What engine does it have and where on the top is th water coming from? (front, back, or side)
Heater core? Inlet or outlet hose fitting at heater core?
May have a bad water pump, otherwise make sure your coolant system has pressure. this can cause over heating.
Pull the radiator shroud, remove the serpentine belt, remove the fan from the water pump shaft, then remove the water pump.