Excusemy ignorance as I know there are many threads on the heater core etc. , but I believe my trucks symptoms are a little different. I am having a continuous water leak from my AC drain whether the truck is running or not. It just drips and drips but will eventually stop about a 1/2 hour after the truck is shut off. Heat and AC work great. Getting to be a PITA having to fill the radiator all the time. Heater core or something else?