Rear window leak

JAP90 · February 22, 2021

19 hours ago, Doolin-Dalton said:

Brother, you're not alone. But be it known, the problem is imho a design issue. There are 16 holes in the roof under that rear spoiler. In addition, the rear window encasement is prone to cracking, something in the design has too much flex, recall those torsional rigidity commercials Chevrolet used to tout. Torsional rigidity requires an engineer and apparently focus groups are designing vehicles these days and not engineers. Everyone's truck is 100% susceptible to this leakage. Driving rain and car wash probably OK. Sitting outside in the rain for days, or covered in snow, you're gonna leak and it's going to ruin the vehicle.

You nailed it. As a mechanical engineer (work in aerospace, not automotive so I've never designed a truck chassis), I am almost certain at this point it is a structural issue with the truck that's not "fixable." If it was as simple as a window supplier problem, it would have been fixed by now -- or window suppliers would be broke from GM passing on all of the repair costs. I had a 2020 AT4 that first leaked after 4 months, then leaked a week after the repair. I watched for leaks every single time it rained and I never went to an automatic carwash. It started leaking the week after getting an oil change -- and being on a lift. I unloaded it and went with a TRD Pro Tundra (while going back 20 years in technology). I feel incredibly bad for anyone having to live through this nightmare -- it's uncalled for and not fun. They are really nice trucks and it's a shame -- I don't know how they sleep at night knowing this is happening. The amount of people that have leaking windows and don't even know it will have a mess one day.

One thing to keep in mind -- my first leak was in the far corner of the window, behind the trim piece above the seat belt. I shined a light from the driver's side to the passenger's side and saw it. Had I been looking around the slider track, I never would have found it. Some are more obvious than others.

I am fully aware that I could be completely wrong, but this has gone on way too long for there not to be a real fix for it yet. And it's clearly not fixed. Good luck to all of you.

Blue5.3l · February 22, 2021

GM most likely just changed the LED’s in the third brake light and cargo light’s for a different pattern to say they did something. Probably all the same mounting holes. Just like the tail lights will be. All to give everything a family look to it.

OnTheReel · February 23, 2021

Eh, they wouldn’t spend the money on frivolous stuff. They don’t spend on anything really. You know they are getting their asses kicked in labor costs “fixing” this leak...so that’s the only reason they would address it.

Spyderwebb · February 23, 2021

I tried the rubber seal that was suggested earlier and there is no way I can fit anything between the spoiler and the roof line. Some areas maybe... but the gap quickly narrows and even prying the spoiler up wouldn't give enough room to squeeze in the seal.

So, I'm going to leave it for the dealer to repair and that has me worried about the quality of their workmanship and if it will do the trick???

So disappointed with this design flaw, Chevrolet!!!! I hope you have people monitoring this thread and that the dealerships are soon given solid repair procedures, but my confidence in you is declining by the day!

Edited February 23, 2021 by Spyderwebb

gemarsh · February 23, 2021

2 hours ago, Spyderwebb said:

I tried the rubber seal that was suggested earlier and there is no way I can fit anything between the spoiler and the roof line. Some areas maybe... but the gap quickly narrows and even prying the spoiler up wouldn't give enough room to squeeze in the seal.

So, I'm going to leave it for the dealer to repair and that has me worried about the quality of their workmanship and if it will do the trick???

So disappointed with this design flaw Chevrolet!!!! I hope you have people monitoring this thread and that the dealerships are soon given solid repair procedures, but my confidence in you is declining by the day!

Maybe there is a difference in how the spoiler fits different trucks. I tried the rubber seal mod and mine was real close also. Could barely get a popsicle stick in between the cab and spoiler. Was going to wait till warmer weather and give it another go. I have the black rtv adhesive/sealer on hand. I go thru a caulking gun tube worth a month. I believe that is MY best bet HERE, for ME. I have a small dealership that doesn't see enough problems, to warrant them screwing with this problem, using my truck as a learning experience.

I just went out and took photos. I was guessing last time saying it was .0625" to .125". Well it eyeballs without using a calipers at .03125". Just right for a bead of silicone.

Edited February 23, 2021 by gemarsh
Spelling

SilveradoRST · February 23, 2021

2 hours ago, gemarsh said:

Maybe there is a difference in how the spoiler fits different trucks. I tried the rubber seal mod and mine was real close also. Could barely get a popsicle stick in between the cab and spoiler. Was going to wait till warmer weather and give it another go. I have the black rtv adhesive/sealer on hand. I go thru a caulking gun tube worth a month. I believe that is MY best bet HERE, for ME. I have a small dealership that doesn't see enough problems, to warrant them screwing with this problem, using my truck as a learning experience.

I just went out and took photos. I was guessing last time saying it was .0625" to .125". Well it eyeballs without using a calipers at .03125". Just right for a bead of silicone.

Is the gap the same measurement across the whole length of the spoiler?

gemarsh · February 23, 2021

9 minutes ago, SilveradoRST said:

Is the gap the same measurement across the whole length of the spoiler?

Yes, across the top. The ends or sides are are closer to .1875"-.250". I can get the .250" rubber seal tucked under the sides with my fingers.

I don't have water leaks, but I'm afraid water is going to set between the cab and spoiler and freeze and then more water added and freeze and finally expand the gap and make the OEM gasket leak.

I can see this area to be a dirt, dust, tree leaf, bug magnet, damming up and letting water stand, not drying up quickly and rotting the OEM gasket or worse yet, a rust out area in the future. My truck will see 99% dirt roads, farm fields compared to asphalt in its life. Have bulk fuel tanks, no need to go to town.

I want to puke when I see some of the photos of big stains on the headliners.

Chrisd534 · February 23, 2021

My rear window defrost isn't working and after multiple trips to the dealer and blown fuses they have decided to change the entire back window. I have 23k on my truck with no leak and I am worried now about the window being changed. Has anyone had success with a full window replacement and is there anything I should look out for?

OnTheReel · February 24, 2021

So the point of jamming the rope seal into the spoiler is to keep water from running under the spoiler and into the cracked window channel? Seems like a band-aid at best.

I know I’m a broken record here, but all data suggests the spoiler itself is rarely, if ever, the sole cause of the leak. Trucks with solid rear windows have the same exact spoiler. And yet to my recollection in 200+ pages I have never seen a solid window truck posted here with a leak.

My hope is that the are redesigning what’s under the spoiler and therefore had to redesign the spoiler too.

SilveradoRST · February 24, 2021

I second the notion that it is rarely the spoiler.

I’ve ran my garden hose over that spoiler with the headliner down for 30 mins each time for 3-4 days. I reused the one time use nuts and still no leaks from their spoiler holes. Not saying it can’t happen but it is really not the main pain point. I even took the spoiler out a 2nd time 2 months later to upgrade to the camera third brake light. Same water test and no leaks from the spoiler holes.

GM needs to ask Fuyao and Vitro to use a strong plastic for the frame.

Edit: And maybe be willing to pay a little more for them when both vendors push back.

Edited February 24, 2021 by SilveradoRST

Transient · February 24, 2021

I second the notion that it is rarely the spoiler.

I’ve ran my garden hose over that spoiler with the headliner down for 30 mins each time for 3-4 days. I reused the one time use nuts and still no leaks from their spoiler holes. Not saying it can’t happen but it is really not the main pain point. I even took the spoiler out a 2nd time 2 months later to upgrade to the camera third brake light. Same water test and no leaks from the spoiler holes.

GM needs to ask Fuyao and Vitro to use a strong plastic for the frame.

Edit: And maybe be willing to pay a little more for them when both vendors push back.

That'll never happen. GM is too practice at saying, "Sharpen your pencils."

Sent from my SM-N960U using Tapatalk

SilveradoRST · February 24, 2021

1 hour ago, Transient said:

That'll never happen. GM is too practice at saying, "Sharpen your pencils."

Sent from my SM-N960U using Tapatalk

Yup I completely agree with you. Just making a point that the spoiler is not the main culprit.

Kclyatt · February 24, 2021

Update....Few months into sealing my rear glass and happy to report no further leaks. I recently sealed up my spoiler as a added guarantee because as we can see GM does not have our best interests in mind. I used door trim from Lowes and this particular type has ridges to help with the trim tool to push into the tight space and also has adhesive on the back to hold into place once set. The third brake light I used clear silicone (same type 3M) since that gap was too tight for trim.

Hope my enthusiasm to prevent future leaks helps another in this exclusive club of leakers!

DarkSky20 · February 24, 2021

21 hours ago, Chrisd534 said:

My rear window defrost isn't working and after multiple trips to the dealer and blown fuses they have decided to change the entire back window. I have 23k on my truck with no leak and I am worried now about the window being changed. Has anyone had success with a full window replacement and is there anything I should look out for?

My entire window got replaced. They brought in a glass guy to do the work. My issue was a foot of sealant wasn’t applied in the top passenger side of the rear window at the factory. I’ve had no issues since replacement. Dealer seemed to take care of me pretty well. No complaints.

Chrisd534 · February 24, 2021

13 minutes ago, DarkSky20 said:

My entire window got replaced. They brought in a glass guy to do the work. My issue was a foot of sealant wasn’t applied in the top passenger side of the rear window at the factory. I’ve had no issues since replacement. Dealer seemed to take care of me pretty well. No complaints.

I'm just worried they'll be creating an issue with the window replacement even though I don't have a leak. Good to hear though!