Running light roof leaks--time to refresh an old topic

[twinmill28]

I need to seal my roof lights--is it just the three center front and back? I'm not thinking you can really do anything with the corner lights? Well, other than I need to put some goop in the front driver corner light where the light bar harness goes in and is no longer sealed.
Do I also need to take the foam off and just seal with RTV from plastic light to metal roof?

 

[Zach]

The usual ones that leak are the three center lights front and rear. I did silicone the left front outer light due to the wiring running through it

 

[twinmill28]

What about removing that little foamy thing? I'm thinking that needs to be taken out?

 

[Zach]

What about removing that little foamy thing? I'm thinking that needs to be taken out?

Yes, remove them. Just make sure you have a good bead of silicone and you will be good. You might want to replace the bulbs while you are doing this.

 

[5gn-h3t]

I would also take out the corner lights and silicone the rubber wire grommet that goes through the roof. I just had a leak on my truck after the "luggage rail" cracked and lots of water was collecting under the corner light and leaking through the grommet.

 

[twinmill28]

I finally got up on the roof to tackle sealing the roof lights/light bar wiring harness and was surprised at what I found.
I'd already pulled one of the three center lights out, so I know what I'd be dealing with. I went ahead and removed the foam from one of the lights and gooped up the silicone and stuffed it back in place (after replacing the light bulbs as recommended). I didn't like the amount of slop that occured without the foam, so I pulled the light, stuck the foam back on and made sure I had lots of silicone covering each of the three holes then stuck the light back in. I did this for the three center lights, and feel pretty confident those suckers will never leak. With those three center lights, there are a total of seven good sized holes in the roof, so now I fully understand how leaks can occur.
I then took off the drivers corner light to determine what kind of massive hole was drilled in the roof to support the light bar harness. To my surprise I found no gaping holes; it turns out the light bar harness is contained in the same grommet as the roof light wiring, and it was securely plugged into the roof with the hole comepletly sealed by the grommet. I wish I'd have taken pictures of this--it's a really clean set-up. The way this is put together now explains to me why HUMMER's were spec'd with light bar wiring versus non-light bar spec'd trucks. I could also see how the harness could be a dealer installed item, but I'm sure it took alot of work to put that harness in if it wasn't done at the factory. Regardless, I went ahead and put some silicone around and in the grommet just in case anything wasn't sealed. While I was in that area, I notice the trim screw that holds the black roof rail trim piece was loose---this seemed like the most likely culprit in my case for why I had water running down the windshield when it rains. I'd been convinced it was due to the light bar wiring, but that really is not the case with how well that was contained in the harness grommit. I went ahead and removed the trim screw and siliconed it and the hole it goes into. I then did the same on the passenger side.
Hopefully, these are the only holes in the front of the roof (other than the sunroof) and I've got everything sealed up tight. Water leaks in Florida are way more urgent than trucks in the West since everything stays wet/damp here for so long after it gets wet.
Thanks for the input on how to deal with this guys----

 

[man1nboat]

I would also take out the corner lights and silicone the rubber wire grommet that goes through the roof. I just had a leak on my truck after the "luggage rail" cracked and lots of water was collecting under the corner light and leaking through the grommet.

Exactly! My drivers side grommet was trashed. I replaced the assembly for $110

 

[MessiaH2]

I thought I was all alone with my H2 dripping from my onstar speaker/mic....LOL

Twinmill28, thank you for the extensive repair description which i am planning on attacking in the next couple weeks. Can you tell me how much time i should set aside for this project?

Another question - when the dealer put the GOBI Rack on back in 03' they left on and went over top of the stock two chrome roof racks... Is that normal? Shouldn't they have been removed? The look really doesn't bother me, just wondering. Thank guys

 

[LoJac963]

I thought I was all alone with my H2 dripping from my onstar speaker/mic....LOL

Twinmill28, thank you for the extensive repair description which i am planning on attacking in the next couple weeks. Can you tell me how much time i should set aside for this project?

Another question - when the dealer put the GOBI Rack on back in 03' they left on and went over top of the stock two chrome roof racks... Is that normal? Shouldn't they have been removed? The look really doesn't bother me, just wondering. Thank guys

I've seen pics of them installed over the factory roof bars....I think it looks terrible IMO. I did take mine off as most of us do when installing a GOBI.

 

[twinmill28]

If you go slow and look everything over to see how it all works, you'll be into it for a total of 30 minutes, tops; and that's really exaggerating it. It'll probably take more like 15 or 20 mins if you just take it apart and silicone it and put it back together. I stalled on this for a long time as I always build it up in my head as being an extensive project, but this one is so simple there's no need to drag your feet.

If it's actually a GOBI, it has it's own brackets that bolt into the roof rail channels and it is totally separate from the roof cross bars--meaning no reason to leave them on. But those lazy bastards probably saw no reason to take them off as unless you know what you're doing, it will take time to figure it out, and time is money. They just wanted you out of there so they could move on to the next job.
I'm pretty sure the only way to get them off now is to remove the GOBI, and while not hard, it takes time, then you have to reinstall it and it is kinda heavy and awkward working that high.

BTW, I didn't mention in my write-up that to remove those three center lights, they are held in by clips and just pop out. They have a notch in the center black piece to use a tool to pry them up, but use caution if you use a screwdriver as you'd be prying on the paint. I think mine just popped out by hand with no extra help.

 

[autumn walker]

I have to go get some silicone and do my front three lights - I have been (not actively) chasing a leak from the front right of the truck since I took ownership.

I think a thick bead around the foam (while still on the truck) should suffice - like caulking a window.

 

[MessiaH2]

Thank for the leak info guys. I will attack that after my lift kit next week :woot:

On the side note about the GOBI. What happened was the dealer ordered in a 2003 H2 and loaded it up with everything they could for a display model. During that first year they "loaned it" to the boy scouts of America as a display for their big functions in the Tri-State area and it ended up with 4,000 miles on it and about $16,000 worth of options no one wanted to pay for, which obviously included the rack that they just installed OVER TOP of the stock racks. I guess i will remove them someday when i am bored because I too believe it would look better and cleaner up there with them off.

I have never really looked at it to tell you the truth. I did look at it when buying it and knew the rack was integrated, so i told the dealer i would buy the truck at $52K (stock price) if they removed the Rack, Third row seat, DVDs and all the options they wanted extra for. Of course they could NOT remove everything but wanted the truck gone so I got the $68,800 Adventure Set Up H2 for $52,000 with all the options!!! I surely was not worrying about HOW the Rack was mounted...LOL

 

[twinmill28]

I have to go get some silicone and do my front three lights - I have been (not actively) chasing a leak from the front right of the truck since I took ownership.

I think a thick bead around the foam (while still on the truck) should suffice - like caulking a window.

I wouldn't recommend doing it that way--the silicone will attract dirt and start looking like crap up there. It only takes a second to pop the lights off, then you're ready to seal under the lights

 

[autumn walker]

I wouldn't recommend doing it that way--the silicone will attract dirt and start looking like crap up there. It only takes a second to pop the lights off, then you're ready to seal under the lights

So when you remove the foam are you "flush mounting" the lights with the silicone between the housing and the paint?

 

[autumn walker]

So I went ahead and sealed my front marker lights with silicone and also re-did my back marker lights... leak persists.



I'm thinking it has to be my windshield - not sure how to go about removing the trim pieces, but that'll be my next place to look next time I get the chance to work on the truck.

 

[twinmill28]

I hope you figured out that it's best not to remove the foam. That "flush mounting the lights" thing didn't work on the first one I did, it just left too much slop between the light and the cab roof so I salvaged the foam and put it back in there with the Amazing Goop to seal it.
Given that didn't fix the leak, your next shot is to work on the corner lights, and like I said, check the screws going into the cab. Mine were loose, so I removed, gooped up with sealant and reinstalled.
Actually, I took everything apart, sealed it and reinstalled--there's not a whole lot on the front roof that can't be taken apart quickly and sealed.
It could be your windshield leaking, but I think it's doubtful unless the installer just did a really crummy job. I was originally convinced it was my windshield until I started sealing the lights.
Good luck!

 

[autumn walker]

I hope you figured out that it's best not to remove the foam. That "flush mounting the lights" thing didn't work on the first one I did, it just left too much slop between the light and the cab roof so I salvaged the foam and put it back in there with the Amazing Goop to seal it.
Given that didn't fix the leak, your next shot is to work on the corner lights, and like I said, check the screws going into the cab. Mine were loose, so I removed, gooped up with sealant and reinstalled.
Actually, I took everything apart, sealed it and reinstalled--there's not a whole lot on the front roof that can't be taken apart quickly and sealed.
It could be your windshield leaking, but I think it's doubtful unless the installer just did a really crummy job. I was originally convinced it was my windshield until I started sealing the lights.
Good luck!

Thanks! I already sealed the grommets under the corner lights - I'm going to start pulling trim around the windshield and also the roof bar track - I hear that can be a source of leaks as well. I'll just silicone everything as I put it back together lol.