Jump to content

Rear window leak

Demon
 Share

Recommended Posts

Jrodpic Enthusiast

Jrodpic

Posted
Posted

https://static.nhtsa.gov/odi/tsbs/2020/MC-10171889-9999.pdf

 

Looking at the pictures from the service bulletin I am convinced it is caused by water running down the top gap of the spoiler. It is either getting in the holes or cracks on top of the window. I am willing to bet that if a gasket/weather stripping was put in to prevent water from getting in that gap it would fix the problem. Someone with a leak should try to measure the gap and use something like this. That’s one of the first things I am going to do once ours if finally delivered.

 

1/16”? 1/8”? 1/4”?

 

https://www.zoro.com/e-james-rubber-cord-neoprene-18-in-dia-10-ft-csneo-18-10/i/G7615781/?recommended=true

  • Like 1
  • Replies 3.5k
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

Rocz3cqg
Rocz3cqg

Sliding Glass or / and Stop Light Module reported Leaking Situation             Contacts

ShamrockShooter
ShamrockShooter

Well my 2019 early build leaker was replaced with 2020 hopefully not leaker. No signs of an leaks on the window or headliner of the 2020 so fingers crossed. Very impressed with the 10 speed after th

Thomcat
Thomcat

No leaker here so can't do a 100% verification, but the problem seems to be with the spoiler design, regardless of weather the sealer leaks or not, and any cracks in the trim make it worse.  

Posted Images

Loner88 Enthusiast

Loner88

Posted
Posted

Mine is at the dealer now for this leak. They claim it's the 3rd brake light gasket. New seal is in but they are waiting for new, revised nuts to reinstall everything. Looking at a week before I get it back, maybe longer.

20201010_092351.jpg

20201010_092345.jpg

20201010_092332.jpg

econometrics Senior Enthusiast

econometrics

Posted
Posted
2 hours ago, Loner88 said:

Mine is at the dealer now for this leak. They claim it's the 3rd brake light gasket. New seal is in but they are waiting for new, revised nuts to reinstall everything. Looking at a week before I get it back, maybe longer.

20201010_092351.jpg

20201010_092345.jpg

20201010_092332.jpg

One of the many “reasons” all of us have heard in our multiple, unsuccessful trips to the shop to get the leak fixed. It’s almost like they know what BS line to give you to try and make you feel like they know it will work... when they know they’ll see you back in a month or two when it starts leaking again. 

Transient Senior Enthusiast

Transient

Posted
Posted

Instead of running to dealership first, has anybody considered having an independent leak test done? It would help you and the dealership figure out what's actually going on.

Sent from my SM-N960U using Tapatalk

Loner88 Enthusiast

Loner88

Posted
Posted
7 hours ago, econometrics said:

One of the many “reasons” all of us have heard in our multiple, unsuccessful trips to the shop to get the leak fixed. It’s almost like they know what BS line to give you to try and make you feel like they know it will work... when they know they’ll see you back in a month or two when it starts leaking again. 

I'm already sort of expecting that.

omegafiler Senior Enthusiast

omegafiler

Posted
Posted

Concerned my new 2020 Sierra Denali 1500 may have this leak as I saw a small amount of water on the plastic portion of the passenger side C Pillar. I couldn't find signs of water anywhere else, but supposedly the dealer is looking at it. 

 

Not exactly reassuring when they claimed to have not seen that issue yet, even after linking the TSB. If they can't find a problem, I'll try to reproduce myself. And get a case/complaint open with GMC directly. Given the repeat TSBs and countless owner reports, they clearly don't seem to be prioritizing the fix for their broken processes that's causing this to happen in the first place. 

RadBrad Enthusiast

RadBrad

Posted
Posted
3 hours ago, omegafiler said:

Concerned my new 2020 Sierra Denali 1500 may have this leak as I saw a small amount of water on the plastic portion of the passenger side C Pillar. I couldn't find signs of water anywhere else, but supposedly the dealer is looking at it. 

 

Not exactly reassuring when they claimed to have not seen that issue yet, even after linking the TSB. If they can't find a problem, I'll try to reproduce myself. And get a case/complaint open with GMC directly. Given the repeat TSBs and countless owner reports, they clearly don't seem to be prioritizing the fix for their broken processes that's causing this to happen in the first place. 

I picked up my 2020 Denali on 8/30/20, its a 8/20 build.  The first day I got it, it leaked from the passenger side rear window, onto the plastic you talk about, and down the window.  I am 100% convinced that most of these power sliders leak on either side.  I had a 2019 Silverado prior, but it had the dark headliner, so it wouldn't have been as easy to notice.  This truck has the lighter color headliner, which is what made me notice the leak first, the wet headliner.  

I took it in to the dealer, and they said "oh yeah" one of these.  Not very comforting lol

Somewhat mutually I decided I didn't want them to tear apart the headliner, spoiler, rear window, caulk etc to basically not fix the leak for good.  I think these repairs just put Band-Aids on if anything.  It would be nice for the 2022 redesign to have a permanent fix for this.  

 

I have had to have my truck towed, due to a battery that lost all its cranking amps (Wouldn't charge at all).  I also am in the build date range for the valve spring issue, hope that doesn't happen!!

 

Good luck with your dealer.  

 

 

 

  • Like 1
omegafiler Senior Enthusiast

omegafiler

Posted
Posted
59 minutes ago, RadBrad said:

I picked up my 2020 Denali on 8/30/20, its a 8/20 build.  The first day I got it, it leaked from the passenger side rear window, onto the plastic you talk about, and down the window.  I am 100% convinced that most of these power sliders leak on either side.  I had a 2019 Silverado prior, but it had the dark headliner, so it wouldn't have been as easy to notice.  This truck has the lighter color headliner, which is what made me notice the leak first, the wet headliner.  

I took it in to the dealer, and they said "oh yeah" one of these.  Not very comforting lol

Somewhat mutually I decided I didn't want them to tear apart the headliner, spoiler, rear window, caulk etc to basically not fix the leak for good.  I think these repairs just put Band-Aids on if anything.  It would be nice for the 2022 redesign to have a permanent fix for this.  

 

I have had to have my truck towed, due to a battery that lost all its cranking amps (Wouldn't charge at all).  I also am in the build date range for the valve spring issue, hope that doesn't happen!!

 

Good luck with your dealer.  

 

 

 

Mine is an 8/16/20 Build, also light interior. More concerned that there wasn't exactly a lot of rain when I noticed this. Which was actually during the test drive, but thought somebody left a window open, until I saw this post (and related TSB's).  

 

If they think they can fix it, I'll let them do what needs to be done and then just make sure they put it back together correctly. Assuming they even make an attempt. 

Duramaxsky Enthusiast

Duramaxsky

Posted
Posted
I picked up my 2020 Denali on 8/30/20, its a 8/20 build.  The first day I got it, it leaked from the passenger side rear window, onto the plastic you talk about, and down the window.  I am 100% convinced that most of these power sliders leak on either side.  I had a 2019 Silverado prior, but it had the dark headliner, so it wouldn't have been as easy to notice.  This truck has the lighter color headliner, which is what made me notice the leak first, the wet headliner.  
I took it in to the dealer, and they said "oh yeah" one of these.  Not very comforting lol
Somewhat mutually I decided I didn't want them to tear apart the headliner, spoiler, rear window, caulk etc to basically not fix the leak for good.  I think these repairs just put Band-Aids on if anything.  It would be nice for the 2022 redesign to have a permanent fix for this.  
 
I have had to have my truck towed, due to a battery that lost all its cranking amps (Wouldn't charge at all).  I also am in the build date range for the valve spring issue, hope that doesn't happen!!
 
Good luck with your dealer.  
 
 
 
What is the valve spring issue?

If you want to find the leak yourself there is an easy way. It will work unless the leak is under the spoiler where you can't get to it. Take trash bags and hang them behind the cab in front of the vent outlets. Tape them in place. Push folded fabric like a towel down between it and the bed to hold the plastic bag against the vent. Turn the fan on high. Spray soapy water where you suspect the leak is. You will get bubbles. With the vents blocked the fan will pressurize the cab.

Sent from my SM-T510 using Tapatalk

RadBrad Enthusiast

RadBrad

Posted
Posted
5 minutes ago, Duramaxsky said:

What is the valve spring issue?

If you want to find the leak yourself there is an easy way. It will work unless the leak is under the spoiler where you can't get to it. Take trash bags and hang them behind the cab in front of the vent outlets. Tape them in place. Push folded fabric like a towel down between it and the bed to hold the plastic bag against the vent. Turn the fan on high. Spray soapy water where you suspect the leak is. You will get bubbles. With the vents blocked the fan will pressurize the cab.

Sent from my SM-T510 using Tapatalk
 

Interesting Idea--thanks for the information!

 

Here is the thread on the valve spring issue

 

 

RadBrad Enthusiast

RadBrad

Posted
Posted
16 minutes ago, omegafiler said:

Mine is an 8/16/20 Build, also light interior. More concerned that there wasn't exactly a lot of rain when I noticed this. Which was actually during the test drive, but thought somebody left a window open, until I saw this post (and related TSB's).  

 

If they think they can fix it, I'll let them do what needs to be done and then just make sure they put it back together correctly. Assuming they even make an attempt. 

Let me know what comes of it...

  • Like 1
JWOutdoors29 Enthusiast

JWOutdoors29

Posted
Posted

Dropped my truck off at the dealer this morning.  I did not get to talk to the service manager like I had hoped since I somewhat know him, but the advisor I talked to seemed to be familiar with the issue.  They called about an hour ago and said they put a simulated shower over the rear of the truck and found a "seam" that was leaking.  They re-sealed it and are letting it cure.  Now they are addressing the headliner as the wet spot/stain is very fresh and hopefully not an actual set in stain yet.  I'm personally hoping they can just clean it and not have to remove the headliner completely.  They are going to call me tomorrow with results.  Fingers crossed it is fixed, cleaned, and no further created problems

Loner88 Enthusiast

Loner88

Posted
Posted

Got mine back today after 6 days. Was not the light leaking like advisor told me but indeed the window per my paperwork. Now I get to argue about the stains in my headliner that I was told would be fixed.

paui4m Enthusiast

paui4m

Posted
Posted
6 hours ago, RadBrad said:

I picked up my 2020 Denali on 8/30/20, its a 8/20 build.  The first day I got it, it leaked from the passenger side rear window, onto the plastic you talk about, and down the window.  I am 100% convinced that most of these power sliders leak on either side.  I had a 2019 Silverado prior, but it had the dark headliner, so it wouldn't have been as easy to notice.  This truck has the lighter color headliner, which is what made me notice the leak first, the wet headliner.  

I took it in to the dealer, and they said "oh yeah" one of these.  Not very comforting lol

Somewhat mutually I decided I didn't want them to tear apart the headliner, spoiler, rear window, caulk etc to basically not fix the leak for good.  I think these repairs just put Band-Aids on if anything.  It would be nice for the 2022 redesign to have a permanent fix for this.  

 

I have had to have my truck towed, due to a battery that lost all its cranking amps (Wouldn't charge at all).  I also am in the build date range for the valve spring issue, hope that doesn't happen!!

 

Good luck with your dealer.  

 

 

 

I agree regarding having mine tore apart.

So, what are your next steps? 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    342,947
    Total Members
    8,960
    Most Online
    Sothpaw27
    Newest Member
    Sothpaw27
    Joined

  • Who's Online   3 Members, 0 Anonymous, 473 Guests (See full list)

  • Latest Articles

  • Posts

    • Grumpy Bear
      Some Assembly is Required

      By Grumpy Bear · Posted

      www.enginelabs.com/news/what-i-learned-today-bearing-clearances-vs-oil-viscosities/     www.enginelabs.com/news/oil-viscosity-can-the-numbers-be-misleading/ The Big Lie… Coming full circle to the reason Lake discusses the Porsche engines in particular. Based on the 2000 samples in the SPEEDiagnostix database, increasing the oil viscosity in these engines, even those run on the track, showed no significant difference in results.   The smoking gun was in the oil chemistry. That is where the data shows higher instances of more wear. Molybdenum was the key; the higher the amount, the less the wear. Speed postulates that higher viscosity oils have more thickeners to artificially inflate their viscosity numbers. These thickeners lose viscosity under shear, and the result is that not all oils of the same viscosity have the same shear stability.   Having enough viscosity is the most important characteristic, but according to Speed, once that required viscosity level is reached, additive chemistry matters more than additional viscosity. Speed also states, oil pressure problems on the racetrack aren’t a viscosity problem; it’s an oiling system problem. Running a thicker oil is just a band-aid for an underlying oiling system problem.
    • Grumpy Bear
      Some Assembly is Required

      By Grumpy Bear · Posted

      Can it still be Assembled II?   Viscosity on the decline by various means. Heat on the rise making that worse. Engine RPM in the tank. Smaller motors with more boost trying to emulate an electric motor. Full torque, zero rpm. Then we will triple the OCI. Argh.    But wait....there is more. LSPI has pushed a shift from Ca to Mg and as that cost more PLUS the run to lower sulfur compounds the TBN is moving in the wrong direction for the increased OCI's demanded.    That not being enough to placate a demand for a parameter they can't measure the other sulfur bearing compounds are also under attack. That would be zinc and phosphorus sulfonate compounds. To some degree those are being replaced with boron esters and others, i.e. titanium ect. All of which have shorter service lives. And there there is the "Secrete Sauce" marketing for AW adds that 'Can't be detected by UOA's" but trust me because I (the blenders) never ever lie.    Spoiler alert; ALL additives are sacrificial! Smaller amounts of the old blended with less robust versions of the new do not equal longer service lives. So what are the blenders recommending? Wait for it.......   MOVING THE GOAL POSTS! OMG      Let's declare the long standing TAN/TBN crossover irrelevant and tell people that soot is a great 'graphite' based lubricant which can aid tribo films. Wait, what? Let's declare that the standards used for oxidation and nitration were to conservative and can be expanded. Let's tell them that because GDI fuel dilution, although being a VISCOSITY KILLER and an acid generator is actually okay because we have better base oils that limit viscosity failure limits. (Said knowing this is measured in fractions of a centipoise and in bases not commonly used in shelf oils)   Lying from the heart is not just the new normal but we have a public, a very young public, that is so ignorant of the facts and so sure of their "RESEARCH" into AI driven models base in regurgitated  instead of scientific research based unvarnished, peer reviewed FACTS that the incoming guard is loosing their grip on reality and the OEM's are tickled pink while the blends bend the knee.    You have an ever limited set of tools to work with. And sooner or later those will be taken from you as the API and the EPA strangle the last remaining fluids from the system. What you have left is your wits. If you care to use them.    At some point in the very near future it will not longer be possible to do "What is best for the machine", and be replaced with "The best you have access too". You WILL be rewarded with half the life and twice the cost. That isn't that hard to predict.         
    • Chuck FB
      Software Update

      By Chuck FB · Posted

      I trust you saw the other comment where he knew what he was talking about !. Yes, these darned newer vehicles with all their so smart they are stupid technology, goes and drains the battery down. As you might see my other comment, I installed a Noco 5 battery tender under the hood and at this point still have the cord routed so I have to lift the hood and then plug it in but am typically parked in a garage or a shed so its not risking the engine hood in the wind. That way I am assured or hopefully so of not finding I have a battery drawn down and can't even start the truck and that also damages the battery to draw it down too far. 
    • Chuck FB
      Software Update

      By Chuck FB · Posted

      I guess no surprise my guesses were wrong !, at least now I know if I ever happen to see it grayed out in my own truck as to what is going on.    I never happened to catch my truck with it grayed out, it seemed every time I would test to see if there was an update it never found anything and yet more than once I would check to see if there was an update and there was nothing, then a day later or even that same morning I would drive to town and after more than one engine shut down in town as I did my errands it would pop up that there is an update now ready to install and the only place I have a connection to the internet is at home by wifi so its not as if it grabbed the download while driving. I don't trust these new vehicles due to all the crap they can decide to do while sitting for some days not running and run the battery down so most of the time if I know the truck will sit for a few days I plug in the battery tender I have mounted under the hood and so the only time the truck must have downloaded software was when it was sitting in the garage where the signal is awful but I have that tender plugged in and somehow it managed to download it. I honestly detest all this crap, way to easy to leave a person stranded.    Since I don't trust any of it I don't do the install of the already downloaded software until I get home and sometimes have even sat in the truck to watch what its doing as its going through the process to its conclusion as its not like it is set up that it will tell you the next time you fire up the engine that the update that was initialed actually installed or installed properly. Yes I can go into the updates and see the list. After I go through the install where I feel its safe to do so in case it breaks down as a result, I will plug in the battery tender after the fact to recharge as I don't know how much power its taking just to do the install and that can take a while for it to install. 
    • nfisherman
      Software Update

      By nfisherman · Posted

      Thanks for the reply. All settings were correct and the engine was off, as it was supposed to be. It turned out to be something simple. I took a drive for about an hour. I must have had a low battery without knowing it. The voltage gauge on the display looked ok. At the end of my drive, I shut off the engine and the update prompt came up and it updated normally. It’s ironic because one of the features of the update is a reduction of battery drain. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...