Hello all,
I have had a water leak develop at the drivers side corner cab light. Over the past 2 years I have sealed all the light grommets and had no issues till this past winter. I replaced the cabin weatherstrip and I thought it helped and it did but it still drips and gets my headliner wet. Today I directed water directly on the channel that runs under the corner light and I created the leak.

directed water flow

weeping out from my cabin strip

can't see but water is dripping from the area of my oil sticker
I will take apart my corner light again but I did last week and the grommet is sealed like crazy. Any ideas of what to look for? Has anyone had this issue? My plastic housing has two hairline cracks but I sealed the sh*t out of them inside and out.
Any suggestions will be appreciated.

Kevin

 

Possible that the sealant on the windshield itself has developed a leak. I've had that happen before on a replacement one before.

 

Hey Kevin,
My 2009 H2 SUV Lux started leaking just above the driver side "A" piler about 2 years after I had it. Dealer Sealed all the marker lamps and even replaced the windshield (Done by (Safelite) at the dealership. It still leaked down the road again. Then the dealer dropped the front of the headliner and told me there was a bad pinch weld in the area between the roof and side panels. Then Down the road it still leaked.

What I have found out is that where the water runs down the roof bar channel ( Where you have your hose) channel under the marker lamps is how the water is getting in. I managed to if I can remember right lift up or remove...( I can't remember now) the plastic molding that faces out above the door. When I got it lose or off it was filled with pine needles and gack. I cleaned all of that out. I think the water runs down the roof bar channel and under the marker lamp and then is diverted under that plastic trim above the door and then it flows to the plastic trim on the windshield down into the door frame A piler and out to the ground.

Any way.. I installed a piece of screen (Like Screen Door Screen) into the channel next to the marker lamp to keep stuff out. I used some Black RTV to mold the screen in.

To some it all up... It still leaks a little during Hard rain. Also... Check you rear Marker outside lens. Pull them off and seal up that rear Wire Grommet. It is hard to get to the complete grommet with RTV. So I bought a Can of pressurized RTV with a long nozzle. Kind of expensive. This way it shoots right in and packs up that area.

I think you'll fine that the water flows under that plastic molding and you'll be surprised how much gack is under that molding...Just My $.02 Worth.
If any one else has anything to add..... Feel free...you'll be helping Kevin And I.

 

I've been chasing this same issue for two years. New windshield, all new door moldings, corner cab lights sealed very tightly, everything I can think of has been triple checked and sealed, and I still get the corner water build-up dripping out the bottom of the interior grab handle. Both sides now ,only when raining very hard, snow melting on top of cab or certain drive through car washes.

I've read many posts that have had GM engineers try to diagnose the problem, and no go. It seems so simple to diagnose, but is a real pain in the ***. This summer I plan to take out my headliner and find the damn leaks once and for all.

 

Not easy but on mine, I did have a roof panel seam leak at one point. I totally removed the entire roof rack, rails, etc and used 3M seam sealer on the seams under the rails. Good bit of work to remove it all though.

 

I'm in the same boat you are read my post....Looks like I'll be doing the Roof rail removal thang.

 

Maybe you could explain a little more. Did you scrape out the old sealing compound? Is that what all the work was about? Were the roof tracks hard to remove after you slid the bars off?

Would be nice to see some pic's if you took any. How about a Blow By Blow description of the job...Short form.

Thanks

 

That was unfortunately one procedure I did not take any photos of and it was a few years ago. So just going from memory...

Pull the corner lights and cross bars off.
If I remember right there are some screws that attach the plastic parts to the metal rails but I could be wrong.
I did remember that there are some torx screws that attach the tracks to the roof.
I also seem to remember that a couple of those screws were pretty corroded and hard to remove but I did get them all to come out.

This is the seam sealer I bought and used (in white)
Once I had the tracks totally off I did not try to physically remove any of the existing factory applied seam sealant as it is pretty hard. I scrubbed the entire seam area clean, rinsed, then a final wipe down with isopropyl alcohol. Then applied the new seam sealer over all edges and let it sit for a day before I put things back together. I did also apply a tiny bit around the edges of the rivnuts in the roof that the tracks screw down to.

I did also reseal the corner light grommets which were basically hard and somewhat loose in the holes. I sealed those with a urethane marine sealant. For the middle lights I put new gaskets on those at one point as well (I made a set of some 3/16" neoprene gasket material I had but they are also available on eBay), many just caulk those but that makes bulb replacement difficult.

 

Thank you all for the reply's. I sealed my windshield without luck. Still leaked as I ran water. I then took off my roof rail on the drivers side including the front and rear corner light looking for a seam like MixMan suggested. Could not find any real reason for water to leak in. I then found a small seam from the front of the windshield past the front side marker light. I saw a ever so fracture of the seam. As I do I sealed the sh*t out of it using RTV sealant. Ran water over it for 45 minutes no leak. Waiting for a good rainstorm to really check before I put it back together. Thanks MixMan I think this solved it. The pics below show where I sealed it.



On closer look I may have to trim some away so My corner light fits properly. I used RTV because I had it on hand.. Will this work...or should I use seam sealer? I dont want to have to do this again.

Thanks for any suggestions,

Kevin

 

Great you found the source of the leak. Not so great looking, and RTV is NOT an adhesive!
Permanent solution is to remove that mess, and get a quality self leveling seam sealer, also tape it off to make a nice clean professional look. GL