DIY sliding window leak permanent repair

Jglew82 · February 19, 2023

Preventatively did this method on my ‘23 this past Wednesday. Thanks for the detailed guide and providing hope this won’t be an issue like it was on my ‘21!

Couple notes on the spoiler reseal:

1. Those 2 lonely seals they include are only on the 2 yellow clips

2. the threaded holes for the 4 outboard bolts seem to have embossed rubber washers on the standoffs, which actually seem pretty good. I applied sealer anyway.

3. I removed all the body plugs, applied light sealer to them as well. Taking no chances!

Edited February 19, 2023 by Jglew82

DHBWA · March 12, 2023

Just finished my ‘19 Silverado that had several minor leaks. Total of 5 cracks. 3 were fairly large.
I have done lots of caulking on several home projects and when I built engines.

I laid in a goodly coat of premium clear silicone and top coated it with the w/s sealer. I can’t imagine how it could leak.
my only reservation (after putting it back together) is I didn’t put any sealer around the two plastic alignment pins nor the four bolts.

I honestly didn’t think about those alignment pins….The bolts have a built in seal so less concerned about those.

edit—

I just figured out the pins wouldn’t need sealer…

Edited March 12, 2023 by DHBWA

Chrisd534 · April 5, 2023

Quick question(s) .. Is 1 tube of the seam sealer stuff enough? And do you need the special gun for it?

Also would it be comparable to 3M 08307 seam sealer or would you think sems is better?

Edited April 5, 2023 by Chrisd534

Pacfanweb · April 10, 2023

On 4/5/2023 at 11:52 AM, Chrisd534 said:

Quick question(s) .. Is 1 tube of the seam sealer stuff enough? And do you need the special gun for it?

Also would it be comparable to 3M 08307 seam sealer or would you think sems is better?

3M is fine. One should be plenty.
I don't use that type when I do it, I use Kent Automotive High Tech Clear, but I see folks having success with the 2-part, so it should be fine, just clean, clean and clean it some more with solvent.

And seal every single thing that pokes through the roof on the spoiler. The nuts have sealer on them, but most of it comes off and the GM TSB tells you to replace them because of that. Definitely seal them.

Also be sure to tape off the plastic around the sliding window. If you get sealer on it and have to clean it off with solvent, it'll take the shine off of it.

Edited April 10, 2023 by Pacfanweb

Chrisd534 · April 11, 2023

On 4/10/2023 at 10:09 AM, Pacfanweb said:

3M is fine. One should be plenty.
I don't use that type when I do it, I use Kent Automotive High Tech Clear, but I see folks having success with the 2-part, so it should be fine, just clean, clean and clean it some more with solvent.

And seal every single thing that pokes through the roof on the spoiler. The nuts have sealer on them, but most of it comes off and the GM TSB tells you to replace them because of that. Definitely seal them.

Also be sure to tape off the plastic around the sliding window. If you get sealer on it and have to clean it off with solvent, it'll take the shine off of it.

Thanks for the tips.. Any cleaning solvent you recommend?

Also for the liner can I just drop the back or will it crease the liner

Pacfanweb · April 12, 2023

1 hour ago, Chrisd534 said:

Thanks for the tips.. Any cleaning solvent you recommend?

Also for the liner can I just drop the back or will it crease the liner

I use brake parts cleaner, but a good wax/grease remover would probably be better. You can usually find the 3M version in parts stores.

The headliner: Be sure to remove the coat hooks, and seems like there's a dome light in the rear that might need to be removed as well. Been awhile since I pulled one of the headliners now. Usually if you bend the liner it will crease temporarily, but unless you leave it that way for a long time, it'll eventually iron itself back out once it's back in place.

Mshawn · June 29, 2023

On 1/15/2022 at 4:22 PM, Leevon said:

This is my 2nd Trail Boss with a leaking slider, both of them I bought new. The first one I fixed myself by replacing the slider with a solid window (details are somewhere in the massive leak thread). The second one I wanted to keep the slider and permanently seal before it ever leaked. I've had the truck over a year and finally got around to it. Since I was dropping the headliner I also added the camera rearview mirror and hard-wired my radar detector.

I dropped the headliner and removed the spoiler. I cleaned the top of the window channel with all purpose cleaner and a detail brush and dried it. I taped the top of the glass and back of the cab with some little tape ball dams at the ends. I warmed the area up with a heat gun so it would flow then I applied self-leveling sealer SEM 39387 then I hit it with the gun a little more to draw out air bubbles. After that cured, I put 3m strip caulk on all of the spoiler bolts and nuts and re-installed the spoiler. The self-leveling sealer had the exact effect I wanted, it bridged from the glass to the body and covered up the plastic slider frame that cracks and leaks. There were no cracks in the frame this time. I also noticed they are putting a little sealer on the nuts that hold the spoiler on, but it's not adequate. The way I did this it should never leak from the glass or the spoiler holes.

The mirror upgrade was easy, swap the brake light, add the cable and swap the mirror. Plug-and-play.

I’ve been a tech for 36 years. I restore and build a lot of car bikes trucks! This is some great work. Thank you for this write up. One hell of a job. I just bought a 2023 Silverado RST, Texas edition. It has the sliding rear window. I was looking at that as a leak problem last night at the dealership before I sign the papers! Salesman was cool and said yes there had been some leak problems but someone on line has a solution. I googled it and this write up came up. Salesman has a RST with the same back window that is how he knew about this problem. Again thanks for putting this write up out there!

Mshawn

Edited June 29, 2023 by Mshawn

Leevon · July 19, 2023

Glad it was helpful man!

Famak · August 2, 2023

Out of 5 sierra 1500, no leaks I guess I'm lucky

DHBWA · August 2, 2023

2 hours ago, Famak said:

Out of 5 sierra 1500, no leaks I guess I'm lucky

All five are 2019 or newer and have sliders?

That would be a miracle. If yes, have you inspected them closely..?

Famak · August 4, 2023

They were/are, 2017, 2018, 2020, 2023, 2023

DHBWA · August 4, 2023

3 of 3 without issue is real good!!!!!

ShotgunZ71 · August 15, 2023

Anyone ever tried just filling the gap between the spoiler and roofline with clear silicone? Not removing the spoiler, just pumping in silicone all along the top. If so, how did it do?

This could be a decent proactive measure or repair.

DHBWA · August 15, 2023

I thought of that but in a driving rain you will still get water on top of the slider. Another issue is unless you do a REAL clean job dust will collect on any overage and look crappy. Ask me how I know…..

ShotgunZ71 · August 15, 2023

2 hours ago, DHBWA said:

I thought of that but in a driving rain you will still get water on top of the slider. Another issue is unless you do a REAL clean job dust will collect on any overage and look crappy. Ask me how I know…..

My thinking was that if you have enough between spoiler and roof, most of the water would have to go down the channels on the sides, instead of rolling over spoiler and then down to the top of the slider. What was your test and results, other than dust collecting on the silicone?