Moon Roof

SpartanUSA25 · Sep 2, 2025

Hello,
2 weeks ago I bought a 2024 Hummer EV 3X Truck. This past weekend we had a bunch of rain and I noticed water was coming in through the moon roof panels. I this something common or has anybody else had this problem. Looking for advise or information.

OmegaHummvee · Sep 2, 2025

Take it to the dealer. There’s a Service Bulletin related to this issue.

I wish you luck though. In a couple weeks mine goes back in for the third attempt to fix the roof leak. Each attempt has actually made it worse. I don’t think this attempt will resolve it either.

SpartanUSA25 · Sep 3, 2025

Thank you the information. I have scheduled mine to be taken in and worked on. I also looked up the bulletin you mentioned and mentioned it to them as well, so we shall see.

Big E · Jan 12, 2026

The actual Customer Satisfaction Program number for the roof leaking is N222378440. And just a note, it doesnt matter whether or not the vehicles 3 year bumper to bumper has expired....that reference number covers any issue. It is GM's way of saying " we know there is an issue and we screwed up". Bought mine 2 weeks ago, drove it 1 day...water dripped on my pants and a cup holder had 1/2" of water in it and this was after it sat in the garage for 4 days. Now its been sitting at the dealership garage for 6 days being repaired ( I hope ).

super8 · Jan 14, 2026

Big E said:
The actual Customer Satisfaction Program number for the roof leaking is N222378440. And just a note, it doesnt matter whether or not the vehicles 3 year bumper to bumper has expired....that reference number covers any issue. It is GM's way of saying " we know there is an issue and we screwed up". Bought mine 2 weeks ago, drove it 1 day...water dripped on my pants and a cup holder had 1/2" of water in it and this was after it sat in the garage for 4 days. Now its been sitting at the dealership garage for 6 days being repaired ( I hope ).

What year is your Hummer? I haven't had this issue on my 2025.

Big E · Jan 14, 2026

2022....when I dropped it off...6 Hummers between 2022 and 2024 were all in for the same leak issue. The bad news is the only Hummer tech they had on site is out at Hummer school being trained.

super8 · Jan 14, 2026

Big E said:
2022....when I dropped it off...6 Hummers between 2022 and 2024 were all in for the same leak issue. The bad news is the only Hummer tech they had on site is out at Hummer school being trained.

Hopefully they’ll get everything taken care of for you. I still wish there were a way to deal with the missing gutters. Nothing like opening the door and having water dump on you.

src · Jan 17, 2026

Big E said:
The actual Customer Satisfaction Program number for the roof leaking is N222378440. And just a note, it doesnt matter whether or not the vehicles 3 year bumper to bumper has expired....that reference number covers any issue. It is GM's way of saying " we know there is an issue and we screwed up". Bought mine 2 weeks ago, drove it 1 day...water dripped on my pants and a cup holder had 1/2" of water in it and this was after it sat in the garage for 4 days. Now its been sitting at the dealership garage for 6 days being repaired ( I hope ).

This is not true I have a 2022 and had a water leak “fixed” that was coming through the front sky panels under the bumper to bumper warranty. The warranty expired and now it’s leaking in the back sky panels. I asked GM service if the leak is covered in the back area through the N222378440 customer satisfaction program and they flat out said no. I would suggest to anyone who owns a Hummer to keep testing the roof panels and if there’s a leak get it fixed while still under the bumper to bumper.

Big E · Jan 17, 2026

src said:
This is not true I have a 2022 and had a water leak “fixed” that was coming through the front sky panels under the bumper to bumper warranty. The warranty expired and now it’s leaking in the back sky panels. I asked GM service if the leak is covered in the back area through the N222378440 customer satisfaction program and they flat out said no. I would suggest to anyone who owns a Hummer to keep testing the roof panels and if there’s a leak get it fixed while still under the bumper to bumper.

Big E · Jan 17, 2026

I would not give up that easily. My first attempt with the first technician also turned out to be a big fat "No can do ". Then I made a phone call to GM customer service and they made a phone call to the dealer that said " no " and changed it to a " yes ". Customer service info is attatched.

src · Tuesday at 12:22 PM

Thanks for the number, I called and they told me if my bumper to bumper warranty is expired I’m SOL for getting that leak fixed.

Big E · Tuesday at 5:03 PM

Sorry to hear that...I just bought my 2022 the first part of January...24000miles, bumper to bumper already expired. They bent over backwards to accommodate me...not only a roof leaking but they also replaced my power tonneau cover because it had a CSP number associated with its defect. I'd try a different GM dealership.