Truck A/C Drain Leaks In Cab

Reader Question: I have a Dodge 3/4 ton deisel pick up have checked the drain on the evapator coil box its just a straight pipe discharge at outside of box it is not restricted .

The older units had a drain hose with 90 degree bend in hose and a collapsed end on end of drain hose . dodge dealer parts dept. Said they dont use that system any more. Also the dealership could not give a fix for water on the carpet, found a drain hose to install onto coil box what else could I look for. thanks Ray


Hi Ray,

I am assuming you have ruled out the possibility of a leaking heater core, and are sure this water is from the A/C drain and not a coolant leak….correct? If water from the a/c drain is leaking inside the cab I would blow compressed air up through the drain opening under the vehicle to try and clear what ever it is that has stopped up the drain.

There could be dirt and debris that has accumulated inside the evaporator case that is causing the blockage. A few good blasts of high pressure air from an air compressor can sometimes be just enough to remove the block.

If that does not do it, you will probably have to remove the a/c evaporator case and clean and reseal it. Your problem is most likely inside the case, and not outside on the drain itself.

Austin Davis

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