Recently i was installing a sub when i discovered that my entire passenger side carpet was soaking wet all the way through and pooling in the floorboards all the way to the back but it starts to kind of thin out into the corner as it gets to under the rear seat and in the front its almost over the tranny tunnel. I saw that maybe the ac drain was plugged up so i took a straw off of a pb blaster can and shoved it in to see if it was clogged. nothing. Maybe i need something longer. I ran the truck for 10 minutes with the ac full blast and no water came out of the drain nor could i locate where it was coming out inside the truck. Im not sure what the symptoms are of a bad evaporator but the ac works fine and blows cold. If anyone has suggestions that would be great. Its driving me absolutely NUTS

 

Can you tell if what you are finding is water or condensation from the A/C? Does the heater box feel wet. Also has it been raining or gone thru a car wash? I'm guessing you may have a water leak from maybe a door seal or from the third brake on the cab. You could run some baby powder around the door seal and run a garden hose around the door at low pressure.

 

It's not antifreeze is it? If so you heater core is leaking. When you ran it did you check inside under the hvac box to see if it was coming out there?

 

Thankfully it isnt antifreeze. I didnt check it when i ran it, i checked right after i took it for a drive. i was looking to see if it came out and saw nothing. The heater box felt a little damp like slight condensation but it wasnt too crazy. My dad owned the truck before me and he said he had the ac leak into the cab when it was new and they fixed it under warranty so i thought maybe it was acting up again. Ill have to strip the interior this weekend because of how wet the carpet is. My door is also really rotted on the passenger side but it has been for a while so im not sure if the door would be a culprit but i can give it a try. I also had a rear window replaced and i put in a new third brake light but this was a while ago and i had no sign of leakage then but i can always check. it doesnt hurt

 

So it is the ac. I figured it out on the way home from college. The heater box is wet but not terrible. Down where the drain goes is wet but it also drains out to the outside to a little bit. Not sure if it’s clogged or what

 

There is a gasket that goes behind it(between the box and the firewall). There have been other with the issue where the gasket deteriorates and water fallows the drain back into the cab. Try getting a rubber elbow and put it on the drain, It will keep the water from draining back.

 

so after a long while i stripped my interior and hung the carpet out to dry and stopped the starting rust in the floorboards. Then i took a hose and sprayed directly into the drain to unclog it and put a rubber hose on it and tested it out and all good. no more water. put the carpet back in and good to go. Thanks for the help guys