UPDATE: This fix is still working, it's bone dry 3+ years later.
I had water leaking into the cab from the windshield. It was a replacement windshield that was in the truck when I bought it. It didn't have the sealant/adhexsive as specified in the FSM. I noticed the carpet in the driver footwell was damp in the corner, and I would actually feel a drip on my foot from under the dash on occasion. Looking at the bottom interior corners of the windshield, I could see moisture, or a tiny puddle, in the corner where the windshield met the seal.
So, the water was leaking from the outside, migrating under the seal where the windshield met the seal, then going under the seal, under the windshield itself, and then coming out between the windshield and the seal on the interior. I have not found a leak from the sheetmetal side of the seal, even though it was not sealed either.
I tried to fix this two autumns ago, by using a "windshield silicone" that you can find with all the RTV tubes at the local autoparts store. This was a "flowable" silicone, that ought to flow into the leaky areas and seal it. I used this on the exterior along the seam where the windshield met the seal. I did not lift the seal and apply under the seal. This worked for a couple days, and overall reduced the volume of the leak, but was not successful.
Recently after posting up the windshield replacement PDF for another member, I decided to try to find the correct sealant and just apply the adhesive/sealant under the seal as noted in the FSM. I could not find the correct sealant in less than a case size online, so I looked for a Polyurethane adhesive locally. What I came up with was PL Polyurethane Roof and Flashing sealant in Black, from the paint supply area of Home Depot. It looked like it would do the job. You will also need cheap caulking gun.
First, I used a razor/scraper to try to get rid of the "flowable silicone" I had used before, then I used my finger to lift the seal and cleaned the seal and the windshield mating surfaces the best I could, using a dry cloth. When it was fairly clean, I used alcohol on a cloth. It actually felt like my seal may have been the original and had some adhesive residue on it from the original factory windshield. You can only get it so clean, so it would be better to have it done correctly with the install.
Next, I took some painters masking tape and put it on the winshield where it met the seal. I let it overlap the seal and then took a razor along the edge and peeled the tape off of the seal, this left me with a tape covering the edge of the windshield, to make it easier to keep the windshield clean.
After one last wipe of the seal/window mating surface with a clean cloth, I inserted the tip of the adhesive tube in the top center of the outside windshield/seal and started squeezing, I kept the tip"deep" and let the adhesive ooze out a bit, as I ran the adhesive around the windshield. I tried to make sure that there was a good mount of adhesive and no gaps. You can always cut/clean the extra adhesive, so be generous. When I finished, I gently pressed on the seal, just enough to make sure there was enough sealant to ooze out a bit, and make sure there were no areas where the seal was lifted up due to too much sealant.
It takes 7 days to fully cure, and you will smell it for about that long, it is strong at first, but not "deadly" as far as I can tell. After about 12 hours, I removed the tape, and did nothing else, but I did drive it with no issues. It will skin over after about 24 hours, and I think you would be OK in rain at that point, as it uses moisture to cure anyway, and I think the adhesive instructions makes mention of using it in wet locations.
I did this about a month ago, and it is bone dry inside. Hopefully, it will hold up in the long term, and I think it will. We have had some serious rain in the past month and it is always parked outside, so my expectations are high.
***Here is a link to my post with the FSM install document: Click here***
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I had water leaking into the cab from the windshield. It was a replacement windshield that was in the truck when I bought it. It didn't have the sealant/adhexsive as specified in the FSM. I noticed the carpet in the driver footwell was damp in the corner, and I would actually feel a drip on my foot from under the dash on occasion. Looking at the bottom interior corners of the windshield, I could see moisture, or a tiny puddle, in the corner where the windshield met the seal.
So, the water was leaking from the outside, migrating under the seal where the windshield met the seal, then going under the seal, under the windshield itself, and then coming out between the windshield and the seal on the interior. I have not found a leak from the sheetmetal side of the seal, even though it was not sealed either.
I tried to fix this two autumns ago, by using a "windshield silicone" that you can find with all the RTV tubes at the local autoparts store. This was a "flowable" silicone, that ought to flow into the leaky areas and seal it. I used this on the exterior along the seam where the windshield met the seal. I did not lift the seal and apply under the seal. This worked for a couple days, and overall reduced the volume of the leak, but was not successful.
Recently after posting up the windshield replacement PDF for another member, I decided to try to find the correct sealant and just apply the adhesive/sealant under the seal as noted in the FSM. I could not find the correct sealant in less than a case size online, so I looked for a Polyurethane adhesive locally. What I came up with was PL Polyurethane Roof and Flashing sealant in Black, from the paint supply area of Home Depot. It looked like it would do the job. You will also need cheap caulking gun.
First, I used a razor/scraper to try to get rid of the "flowable silicone" I had used before, then I used my finger to lift the seal and cleaned the seal and the windshield mating surfaces the best I could, using a dry cloth. When it was fairly clean, I used alcohol on a cloth. It actually felt like my seal may have been the original and had some adhesive residue on it from the original factory windshield. You can only get it so clean, so it would be better to have it done correctly with the install.
Next, I took some painters masking tape and put it on the winshield where it met the seal. I let it overlap the seal and then took a razor along the edge and peeled the tape off of the seal, this left me with a tape covering the edge of the windshield, to make it easier to keep the windshield clean.
After one last wipe of the seal/window mating surface with a clean cloth, I inserted the tip of the adhesive tube in the top center of the outside windshield/seal and started squeezing, I kept the tip"deep" and let the adhesive ooze out a bit, as I ran the adhesive around the windshield. I tried to make sure that there was a good mount of adhesive and no gaps. You can always cut/clean the extra adhesive, so be generous. When I finished, I gently pressed on the seal, just enough to make sure there was enough sealant to ooze out a bit, and make sure there were no areas where the seal was lifted up due to too much sealant.
It takes 7 days to fully cure, and you will smell it for about that long, it is strong at first, but not "deadly" as far as I can tell. After about 12 hours, I removed the tape, and did nothing else, but I did drive it with no issues. It will skin over after about 24 hours, and I think you would be OK in rain at that point, as it uses moisture to cure anyway, and I think the adhesive instructions makes mention of using it in wet locations.
I did this about a month ago, and it is bone dry inside. Hopefully, it will hold up in the long term, and I think it will. We have had some serious rain in the past month and it is always parked outside, so my expectations are high.
***Here is a link to my post with the FSM install document: Click here***
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