I have a 2006 F-150 Regular cab with A/C. It appears I also have a leak in the firewall or possibly in the plenum. Not sure which. The leak results in a puddle on the passanger side floor. About a cup in 24 hours whenever it rains, even when the truck has been parked. I can feel what appears to be a penetration stuffed with an open cell foam product. located on the firewall near the tunnel side. I can't tell if this is the source or it's located higher up and running down as I can't get my hand higher.

Can someone enlighten me about this? Is it a common problem? Does anyone have experience with this type of problem. I bought the truck used w/o dealer warranty last month and this is the first rain I'd experienced. There is about 5 weeks of Mfgr warranty remaining. Would something like this be covered?

Thanks for any consideration you might lend to this question.

 

My 06 F150 had a leak similar to what you describe. After 6 trips back and forth to the dealer, they discovered the source was a body seam not sealed properly. They had to completely remove the entire dash and all the HVAC components in order to reach the area of the leak and seal it. My leak was fixed under the 3/36 warranty. I don't know if yours would be covered this close to the end of the warranty. I would take in as soon as possible to get it documented and let them get started on fixing it.

 

Thanks KD4CRS:

That's kinda what I'm thinking. I went thru a similar situation 40 some years ago. I'd bought a 1968 Barracuda in Philadelphia and the first rainstorm filled up the footwell on the passenger side. It was winter and it froze. I hasseled with the dealer for a month before he fixed it and it would never have gotten done if the wife haden't taken them to task publically but that's another story. As it turns out they'd missed a weld where the plemum joins the firewall. I'm thinking this is similar because it happens when the truck is at rest and water cannot possibly be driven up unto a penetration.

I'm thinking if yours was fixed under warranty, mine should be as well. I'd planned on documenting it at the dealer on Saturday.

Would appreciate hearing from others that have similar problems.

 

I also found water coming in through a little hole in the psgr side floor up by the black plastic pipe going through the firewall to the heater. The little hole (smaller than a quarter inch that was partially taped from factory) was a little to the right (if you are sitting in the seat) of it. By spraying water in just below the fender splash guard and just above the frame rail. I was standing by the psgr side front tire while spraying towards the firewall. Additionally i found the foam to be wet and allowing some seapage onto the floorboard below and around the black pipe mentioned earlier. Lastly, i found while taking off my splash guard in passenger front fender and the bottom four inches of the fender was filled up with leaves, pine needles, dirt and debris. The little drain point just didn't drain it all. This caused the water to fill up amd become water logged. This was not a cause of my cab leaks though due to the location of my leaks but nonetheless if you pull off your spash guards to do some silicone work on the firewall don't forget to verify your drain in the fender is cleared. The other reason i pulled off the splash guard was to place an elbow on the a/c drain to direct the a/c-hvac drainage from the evap/dryer downward. Prior to doing this the water was being blown back into the draintube. Something i though of is when you put the leveling kit on these pickups the reality of the water flowing the correct way down the horizontal hose is kind of unlikely. So hopefully the elbow on it will allow it to drain out better - especially if you back it into your driveway so the nose of the truck is lower than the rear.

 

Steamjockey... will you post what they find at the dealer please? Hopefully you will be able to get it all fixed up while under warranty. I have found so many leaks on my truck that for some reason all that I have found so far are not all the leaks yet.