Rear Cargo Area Water Leak - How I fixed it.

[2000UZJ]

I had a massive water leak a few months ago. It turned out the rear gasket that goes around the entire tail gate wasn't seated properly. I pulled it off and reseated with silicone. Not a drop since.

When I say leak, I mean water sloshing around in traffic.

 

[Actualeyes]

Now I'm paranoid about my high mount brake light!

Last Hundy I had was cracked (vertically) and I never noticed a leak, but maybe I needed to look more carefully!.

Great post!

 

[smm3]

I had the same problem with water leaking. I thought it was the third brake light so I taped it off and water tested it. I was still getting water. I also pulled the headliner to see if the rear sunroof drains were clogged but they were not.

I figured out that water was coming in under the gasket and trim on the side power windows. I removed the windows and pulled the black trim. I used some closed cell foam over the holes where the trim attaches. The OEM gaskets were pitiful. The trim attaches with those push clips. I made a hole in the closed cell double sided foam and the clip went right through. To me, this was an improvement over the OEM gaskets. I can't believe they haven't leaked before now. It fixed the water leak on the sides.

Little while later the leak returned. At this point I was lost. I pulled the third brake light and bought some 3M sealant to try and reseal the light. It was a TERRIBLE idea. The 3M stuff didn't hold and it was almost impossible to get off. In the end, I just bought the new light...184.00 and now the leak is fixed. If I had to do it over again, I would just buy the light and be done with it.

I also bought a new rear hatch gasket since that was the last thing I could think of that it could possibly be. If someone needs that gasket, I have one I can let go of. I think it was about 75.00.

Good luck.

 

[TXLX100]

Now I'm paranoid about my high mount brake light!

Last Hundy I had was cracked (vertically) and I never noticed a leak, but maybe I needed to look more carefully!.

Great post!

I noticed today the center brake light on my LX has a vertical crack through the lens. Does anyone know if the lens separates from the housing easily? It's not leaking as far as I know. I don't want to spend $250 on a new light right now, so I'd like to just seal it up if I can get the lens off.

 

[dnp]

I noticed today the center brake light on my LX has a vertical crack through the lens. Does anyone know if the lens separates from the housing easily? It's not leaking as far as I know. I don't want to spend $250 on a new light right now, so I'd like to just seal it up if I can get the lens off.

The two 100s I have right now have exactly this same problem (vertical cracks in the lights in EXACTLY the same place), and the last 100 I had had it also! Seems to me this is would be an excellent retrofit opportunity for someone who already makes replacement 3rd brake lights (Dorman, ANZO, etc.) At nearly $200 for TEQ, that's pretty difficult to accept.......

 

[TXLX100]

I think I'm going to pull mine and see if I can get the lens off and seal it from the inside. If it breaks, oh well... It's already broken.

 

[TXLX100]

I finally fixed my cracked high mount light. There are two bolts holding it down to the hatch, and it seems the tension on the housing probably cracked it. The lens and housing were both cracked clean through.

I glued the two pieces together with Duco Adhesive, cleaned off the old gasket as best I could, and made a new gasket out of some dash stuffing sheet I had layng around. Tightening the housing back up, I halfway expected it to crack again, but it didn't and is still in one piece. The real fix is buying a new light assembly, but the cheapest I found was $200 and seems pretty steep for what it is.

 

[Xetabur]

I just washed my LC and I think I figured out why my carpet is getting wet. Looks like it's my 3rd brake light.

 

[merbesfield]

Thanks for the write up. I just got an 07 w only 78K, which was a garage queen. It now is forced to live outside and I have found the right rear cargo wet. Hope this is the solution. Sounds like a PIA job, but one I am forced to do. Thx again.

 

[merbesfield]

Well today I realized that my 07 didn't have a 3rd tailight like the early ones bc it has a spoiler w the light integrated into it. The place where the light would be is filled in w a blanking panel. After have the wife hose down the area I saw water trickling in from left side. I really don't want to have to tear this thing apart. Lazy? Yes! After pulling the rubber gasket I found an area that was crimped over where a blob of factory seam sealer was that was sticking out. There was also a bunch of sealer under the gasket that doesn't look factory to me. Did the factory glue the gasket down or is this the work of a PO. I used Acetone to clean the entire area and scraped off the seam sealer blob, which I think was letting the water in. I replaced the gasket temporarily. Question is do I reseal with silicone or not? Is the gasket supposed to go on dry?

 

[SupraTuRD]

Well today I realized that my 07 didn't have a 3rd tailight like the early ones bc it has a spoiler w the light integrated into it. The place where the light would be is filled in w a blanking panel. After have the wife hose down the area I saw water trickling in from left side. I really don't want to have to tear this thing apart. Lazy? Yes! After pulling the rubber gasket I found an area that was crimped over where a blob of factory seam sealer was that was sticking out. There was also a bunch of sealer under the gasket that doesn't look factory to me. Did the factory glue the gasket down or is this the work of a PO. I used Acetone to clean the entire area and scraped off the seam sealer blob, which I think was letting the water in. I replaced the gasket temporarily. Question is do I reseal with silicone or not? Is the gasket supposed to go on dry?

Could you post a pic of the blanking panel on your '07? Does the 3rd light harness pass through it? I think I would pop it out and thoroughly clean it and then reseal it with silicone since you're already in there... this way you shouldn't have to mess with that part in a very long time. I believe the factory did use a tacky sealant on the backside of the rubber seal. I'd clean it up and squeeze in some of that 3M weatherstrip sealant for that part.

 

[jmaclaug]

Just a tip, which many already know, about how to find a leak anywhere on your rig. Get a bucket of soapy water. Turn your cabin fan to fresh, and crank it up all the way. Close all windows and doors. Mop or rub the soapy water on sections of your rig. Look for the bubbles to find the leak. The fan all the way up will force enough air out to make bubbles which you'll be able to see.
I found a hairline crack on my third brake light which I could not pick up without the soap. Sealed it up, and now my leak is gone.

 

[therealdutch]

Soooo, after a few days of heavy rain noticed our cargo area was nice and swampy. Popped off the trim and hosed down the tailgate/roof and sure enough it was pouring in right below the upper brake light. Pulled it, a few hours later of elbow grease, goop-off, and a plastic "blade" to scrape; silicone bead, reseat the light, and as I'm threading on the second of 2 nuts that hold the light in place, I must have given it one turn too much, or the goop-off got in space that the bolt is attached to and it popped off.

 

[therealdutch]

You can see where it was getting in and running down the trim

All cleaned up and ready for re-install

 

[JACA]

I had a similar leak in my rear cargo area, and suspected it might be from the 3rd brake light. However, I didn't have to remove so much trim and rear spoiler (don't have one). I simply removed the brake light assembly by taking off the two 10mm nuts, and prying the light off the gasket which was dry and crumbly. I scraped all the old foam residue off, and cleaned with alcohol. I put a thick bead of silicone sealant all around the area where the gasket used to be, put the light back in, and tightened up the bolts. I let it dry for 24 hours, and tested it. No more leaks!

 

[dnp]

Unless I've totally missed them somewhere, it's still hard for me to believe no one makes an aftermarket replacement for these lights! Of all the 100s I've had, I don't think I can remember having one that wasn't cracked (almost exclusively more toward the left end). You can buy aftermarket LED lights for just about any application - many of them for even ridiculous uses - but no one I can find has picked up this legitimate need. C'mon Depo, Anzo, etc......!

 

[AvCruiser]

Great info. Thanks, all. I am considering the suggested fix, however, my third brake light shows some warping. Should this factor into my decision to repair v. replace? Also, this truck is new to me and it appears as if the problem had been going on for sometime before I purchased (see photo). I removed the rear seal, lifted and dried carpet in the Va. summer sun after spraying with a vinegar/water mixture, and cleaned the cargo area thoroughly, however, I am wondering if I should be concerned about corrosion under the floorboard as I recall hearing some water "sloshing" around before I figured out the problem? I peaked down through some of the drain holes and it appeared ok, but is there more that I should look for? There is a little surface corrosion on some of the mounting hardware used to attach the seats which I can plan to tackle with some steal wool and wd40. Thanks.

 

[pavieSD]

Great info. Thanks, all. I am considering the suggested fix, however, my third brake light shows some warping. Should this factor into my decision to repair v. replace? Also, this truck is new to me and it appears as if the problem had been going on for sometime before I purchased (see photo). I removed the rear seal, lifted and dried carpet in the Va. summer sun after spraying with a vinegar/water mixture, and cleaned the cargo area thoroughly, however, I am wondering if I should be concerned about corrosion under the floorboard as I recall hearing some water "sloshing" around before I figured out the problem? I peaked down through some of the drain holes and it appeared ok, but is there more that I should look for? There is a little surface corrosion on some of the mounting hardware used to attach the seats which I can plan to tackle with some steal wool and wd40. Thanks.

Remove that rubber seal, it just pulls out, and check your pinch welds. If you have rust, better to catch it now, then wait until it presents a real problem down the line. See my picture/thread for specific details.

Rear Sill Rust

Mark

 

[btbowie]

Great info. Thanks, all. I am considering the suggested fix, however, my third brake light shows some warping. Should this factor into my decision to repair v. replace? Also, this truck is new to me and it appears as if the problem had been going on for sometime before I purchased (see photo). I removed the rear seal, lifted and dried carpet in the Va. summer sun after spraying with a vinegar/water mixture, and cleaned the cargo area thoroughly, however, I am wondering if I should be concerned about corrosion under the floorboard as I recall hearing some water "sloshing" around before I figured out the problem? I peaked down through some of the drain holes and it appeared ok, but is there more that I should look for? There is a little surface corrosion on some of the mounting hardware used to attach the seats which I can plan to tackle with some steal wool and wd40. Thanks.

View attachment 1278487

I ended up going with butyl tape for my 3rd brake light leak. I'm down in VaBeach and it went through tropical storm Colin right after we did it, no problems. Worth a try before you go straight into RTV or any sealant that might be a bit harder to remove if necessary. Re: the rear, Like @pavieSD said just pull that seal back and check it. Mine was nasty like yours and I used a citrus based cleaner and it got everything up. As for the seat hardware corrosion, it's probably fine unless it's full on rust, then I'd replace them. My rear second and third row seats are permanently out so if you want a photo of anything just PM me. Side note: you can just unbolt your seats and take the entire rear carpet out and clean it, worth it if there's any smell leftover from it sitting damp in the heat.

 

[AvCruiser]

I ended up going with butyl tape for my 3rd brake light leak. I'm down in VaBeach and it went through tropical storm Colin right after we did it, no problems. Worth a try before you go straight into RTV or any sealant that might be a bit harder to remove if necessary. Re: the rear, Like @pavieSD said just pull that seal back and check it. Mine was nasty like yours and I used a citrus based cleaner and it got everything up. As for the seat hardware corrosion, it's probably fine unless it's full on rust, then I'd replace them. My rear second and third row seats are permanently out so if you want a photo of anything just PM me. Side note: you can just unbolt your seats and take the entire rear carpet out and clean it, worth it if there's any smell leftover from it sitting damp in the heat.

Thanks for the advice. I completely removed the weather strip, removed the rear carpet and cleaned the cargo area thoroughly. The weatherstrip looks to have some damage due to the excessive moisture exposure but I think I'll just clean it up and re-seal it with Vaseline, rather than spend another $80 for a new one, and keep an eye on it. As for the surface corrosion - what's the best tactic for removing? I was planning to use some steal wool and wd40 or rustoleum? It's fairly light, and assuming I've cured the moisture problem, I don't expect it to get worse, but I'd like to get rid of it.