2015 F150 Lariat, 4wd, 5.0L V8

I believe I have narrowed down a leak down to my driverside floorboards after many months of searching. I believe it to be a windshield leak at the lower driverside corner. I haven't located it yet but will this weekend. Has anyone ever used flow-able windshield sealants to fix a leak in their vehicle? Or have pricing/experience with a leaking windshield repair DIY or dealer?

 

If it's coming in a bottom corner, you may or may not get it sealed externally. Give it a shot, but you may have to pull the glass and have it re-sealed.

 

Should be easy enough to check. Pull off the cowl garnish, put a hose to it, see if water runs in.

Could also be running down from a top corner. Once you find the point of entry, should be easy to seal up. I would cut glass as a last resort, as removing old adhesive and applying new can introduce more potential leaking if it's not done correctly.

 

Do you have the pano roof?

 

I do have a pano roof but the drains appear to be working just fine. When it rains and is colder at night I can actually see condensation on the lower rightside of the interior of the windshield too

 

Is it easy to remove the cowl garnish?

 

If there's a windshield leak, it's most likely from a top corner, since it's a known issue. But if you remove all the trim from top to bottom, then you'd find out for sure where the leak is. Good luck.

 

If it is from the top corner, would the flowable windshield sealant I have work well?

 

When you're checking for leaks with a hose always start at the bottom first and slowly work up, I suspect if it's leaking it will be at the top or maybe the side and running down and pooling along the bottom leaving the condensation you are seeing. When I was installing windshields years ago all we did for leaks was remove any trim that would allow you to see the pinchweld and run a caulking gun with windshield urethane over the joint between the glass and metal in the suspected leak area. It usually worked, use a low viscosity urethane so it will flow better and warm it up if it is cold so it flows easier.