2000red_F150

Okay so I need help from everyone on this website because I can't be the only one with this monster headache of a leak. I know this is a fairly common problem for these 10th gen trucks to have a windshield leak that ruins the fuse box under the dash. I had the entire windshield professionally resealed and put on brand new weather stripping around the windshield as well. There's no possible way for it to leak through it's sealed inside and out on the weatherstripping. Next rain storm, the SOB is still leaking through somewhere. I've taken off my fender and caulked up every possible hole it could get through and still leaking. I've come to the conclusion it could only be the body harness going through the firewall with the 10mm bolt behind the fuse box because I watched water drip through the wire loom under the dash from there. I took one off and saw a little bit of moisture in there so I tightened them all up nice and snug and it's still leaking. This problem has been going on over a year now and I'm honestly about ready to take a Saturday and tear off the entire front end and caulk up every hole I see. Has anyone else experienced a similar issue? I've already had to dry out my fuse box about 3 times and I'm not spending $350 on a new one from Ford until I get this leak taken care of. This is honestly just frustrating me at this point because I have double and triple checked and even tested with a hose every spot it could leak in from. Does anyone at all know where I need to be sealing up at?

P.S. I do have a amp wire through the firewall for my subwoofer but it's not leaking through there that was the first place I checked.

OhioLariat

From your screen name I assume you have a 2000 so this may question be moot, but do you have a sunroof? If so, the drain tube may have pulled loose.

As for your firewall holes, I don't see how that could be affecting things unless you were spraying water up in there. Finding/stopping leaks and squeaks are both a PITA. Good luck!

..

2000red_F150

I have a XLT supercab so no sunroof. I’d love to have one though. I agree with you as well this leak has been a major PITA ever since it started. If only it were as easy as sticking a cork in it

kd4gij

Did you take off the cowl and clean the drain holes? When they took your windshield out did they fix any rust?

2000red_F150

Yes I've taken off the cowl and cleaned the drain holes a couple times. I don't believe there was any rust under the windshield either but then again I didn't ask I think I'll check up on that to make sure.

kd4gij

Take the A pillar trim off. If the windshield is leaking you will see it. Probably run out the corner of the headliner. Or do like I did and take the headliner out also.

WA4x4

I recently have been plagued by water dripping down the cable to the fuse box and GEM. I am about to have the windshield replaced as the two windshield places will not reseal and guarantee the seal on the existing windshield. The Ford dealer wanted to charge hours of labor to evaluate before doing any work.

To me me having a plugged drain hole on the outside should not have a path to the inside of the truck.

1999 F150 Scab

Jbrew

Mine didn't leak at the windshield, it leaked at the cab overlaps under the cowl...like a sive. It was the factory caulk that went bad between the spot welds. I used plumbers putty to surround the area to test.....sure enough, that was it. Both sides of the cab leaked there, the drivers side was the worst. Water trickled down just missing the fuse block while stationary. Concluded that it came in contact when the vehicle was in motion.

PITA to fix it since I had to pull the fenders off. I choose to weld it solid since I didn't have any caulk handy (GE silicon). You can also use body panel glue.

If it's you windshield, Ford uses a product called window weld, heavy at the A-pillars.

WA4x4

When the first readings I took, amp meter on the negative side of the batter, it was 0.80amps on initial hookup the dropping off to 0.40 amps. Getting rid of the drip onto the wiring harness, which had the covering removed by some shop, after one day it dropped to 0.40 then 0.20 amps approx. Put heater inside the cab for awhile. Light rain that night got wet floor mats again but the amp draw was 0.20 initially then after a second or two it dropped down to 0.050 amps or less! Success. Had some more rain during the day, NO wet floor mats. No rain over night, no wet floor mats.

its to be dry today, so I’ll let the heater be in the truck all day (heater is small one, on the floor near the GEM). I’m at the point of getting the windshield replaced, about $250 to eliminate that variable. If I can avoid replacement of the GEM and/or fuse box it’ll be worth it to me.

All the water intrusion mentioned above happened without any movement of the truck.

(I failed to mention that I isolated the current draw to on 50 amp fuse in the engine fuse box that feeds the Fuse panel and GEM).

Thanks to to all that post their work on this forum, it gave me ideas of how to isolate the problem.

Jbrew

2000red_F150, you mentioned caulking under the fenders. This is the only pic I could find. I have better picks somewhere, but this is where the cab leaks were on mine, on both sides, -



Did you caulk or seal this area ? Well, this is what fixed the intrusion problem with my 98.