So I've read a bunch of posts and confirmed I have leaking cab lights. So I'm going to seal those up. I can't find a leak around my windshield but I'm not sure where they normally develop the leaks. Has anyone had the leaking windshield and were you able to determine where it was actually leaking from?

One thing I did find out is these cab lights can leak a LOT of water. It's a terrible design and they seem like they can leak where the light meets the cab but water will also set where the screw holds the cover to the base and when water gets in the light it will eventually leak down and into the cab. I'm going to try to find some replacement lights that are a better design. If I can't I'm going to silicone the crud out of them.

 

Silicone around the lights won't hurt any and if I had to mess with mine they'd get a treatment of it. On the windshield...I think you just soak it with a hose or check it after a good downpour and see if it's leaking. Where it's leaking is irrelevant at this point as the solution is to R&R the windshield and when you remove it you will most likely be able to identify the spot. Then you can clean that up as necessary.

 

One of the first things I did after I got my truck few years ago was to replace those screws with stainless steel screws.
The original screws were loose, and about the only thing with noticeable rust in the whole truck.

 

my 02 had a significant leak. i blamed the cab lights.
well, last summer i took the truck apart to fix the leaks. surprise surprise, after sealing the cab lights, the carpet was still soaked.
so next step was to remove the windshield. once the glass was out, i found the truth behind the wet carpet. both top corner seams were leaking from where the seam sealer failed. middle of the top of the glass seal failed, leaking water in.
both sides, mid way down between corners seal had failed letting water in.
both bottom corners seal had failed letting water in and sit until it rotted a hole about the size of a quarter in each lower corner.
bottom of the glass where the factory clips are that holds the glass in place until the seal drys had rotted out resulting in two holes about the size of a dime.

the complete frame was stripped to bare metal, holes were welded shut, upper seams resealed, frame was then primed and painted, proper ford windshield primer installed, glass seal installed and glass installed, the carpet is finally dry. for 7 months now.
best part is, no more electrical gremlins caused by wet electronics.

 

I've pulled the cab lights and I'm cleaning them and putting them back on using butyl tape and a bead silicone around the bases. Then I'm replacing the bulbs with LEDs and siliconing the top to the base. My plan then is to soak it good with the headliner and pillar trim out and see if I can find any windshield leaks. Thanks for the advice on where yours leaked!

Mike

 

don't be surprised if you see no leaks either. .. i damn near put my truck underwater looking for leaks but never saw one. all i ever got was a wet carpet and electronics from water running down the "A" pillars and under the cowl.
remove your kick panels and fuse box and look for rust on any of the componants. if they are wet or show signs of rust, it is a pretty good bet the glass seal has failed and is leaking too.

 

It's amazing how little water it takes to cause the electrical grimlins in these trucks. After I got the cab light bases sealed up I hooked the batteries up and the blower relay started clicking like crazy and the blower would run with the key off. I pulled the fuse block and gem, opened up the gem and there was not a drop of water in it. I have an extra gem so I put it in and same symptoms. I decided to just put a fan on it and let it set overnight. The next morning, same thing. I pulled the fuse panel again and decided to try to take it apart. The last time I did this it was an epic fail. I used a 1/2" drill bit to remove flange from the stud mounting bolts and gently pulled it apart. This time I was able to disassemble it one layer at a time. Water had penetrated the fuse block and was present between the layers. As I removed a layer I would clean and dry it then put them back together in opposite order. Once all the layers were out I could not get the whole thing back in the case. I found if you put about 3 layers back into the case one at a time you'll come to a point where there aren't a lot of pins that have to line up to put the rest of the plates in as a unit. This did fix the electrical issues. In hindsight I wish I would of put it in the oven at about 150 or so for half a day. I'd say that would of dried it out but now I know I can disassemble and reassemble a fuse block.