2015 Chevy window leak?

[jstone]

I am getting some water in threw the drivers side coming in by the e break. Ideas on what and where to look. Thinking of getting the window taken off and resealed? Ideas

2015 Chevy 3500 HD crew cab gas

[Woodchuck]

I would check cowl drains first. You can check the windshield seal by spraying soapy water around the seal on the outside and then blow air from a compressor on the inside and see if you get bubbles. 

[baker5150]

My 17 leaked from the windshield in the upper corner.  Water worked it's was down to where I saw it dripping onto the floor board and pooled a bit on the dash.
When it sits it'll get the liner wet above the A pillar too.
Took about 40k before I noticed it.
Dealer said they had seen a few like this.

[AROTTY]

99% on a 2015 its coming from the sharkfin antennae. They redesigned it in 2016 due to leaks. I haven't sourced one out of a junkyard yet so for now on my truck i have clear gorilla tape at the seams.

[jstone]

I will try to seal that and see if that helps
Thank you

[jackelope]

It would be really weird for a windshield to just start leaking on a 5 year old truck. It's a pretty rare leak point and 99% of the time only happens on brand new windshields or brand new vehicles.

If you're going to replace the antenna, I'd suggest avoiding the wrecking yard route and replacing it with the updated design. Maybe goes without saying.

[AROTTY]

Yea should of specified that. Replace with 2016-18 design

[TSLPE]

I had a shark fin replaced on my 2008 Duramax and it was over 1000.00. A year after that when it started leaking again an bought an 8.00 tube of silicone and ran a bead around it. No more leaking !

[Tenkara]

99% on a 2015 its coming from the sharkfin antennae. They redesigned it in 2016 due to leaks. I haven't sourced one out of a junkyard yet so for now on my truck i have clear gorilla tape at the seams.

This was the same issue mine had.

[nwmein199]

99% on a 2015 its coming from the sharkfin antennae. They redesigned it in 2016 due to leaks. I haven't sourced one out of a junkyard yet so for now on my truck i have clear gorilla tape at the seams.

Had this problem on my 2014 silverado. Took the fin off, bead of silicone, and all sealed up.

Started with a puddle in the drivers foot well. Kept following the water up through the dash to the shark fin

[jstone]

Just ran a bead of silicone around the outside of it.!
Crossing my fingers that’s it

[jstone]

Thanks again all of you.

Jstone

[Pnwrider]

Do you have a sunroof? That’s another fairly common culprit. The drain ducts get clogged and in comes the water!

[jstone]

No sun roof,

[BrandonWatts]

My 14 gmc was leaking a couple years ago, found it was the shark fin. There is a small notch in the back of the fun that let water in. Put a small bead of silicone on it and the leak stopped. Lot easier then pulling the headliner.

[jstone]

Sealed it. But I think the water must have shorted out a fuse. My dome lights won’t come on when I open the door and the driver brake light and blinker don’t work. I checked the fuses in the engine compartment will check the ones in the door panel tonight.? Has that happened to you to?

[jstone]

Ok had the window shop test the windows all is good. I’m not a mechanic so if the heater core is leaking on the passenger side would it smell like antifreeze?
I took the lower panel out and lifted up the carpet. It is all wet under passenger side. Coming from the fire wall. I soaked up the water in the carpet and padding

[Stein]

I've never seen the 2015, but most heater cores operate by diverting some or all of the coolant through the firewall and heater core and there is a water to air heat exchanger that takes heat from the coolant and pushes hot air into the cabin.

When I have heard water or gurgles in the cabin it is because of this section of coolant line that goes through the firewall and you hear bubbles or air in the line which sounds like running water or gurgles.

If it leaks, it leaks coolant and you would see and possibly smell the slightly sweet smell.

I also had a Suburban with a leak in the windshield that ended up puddling under the carpet on the passenger side.  I never saw any water anywhere except under the carpet, but after crossing everything else off the list we replaced the windshield and dry as a bone since. 

[Crunchy]

Ok had the window shop test the windows all is good. I’m not a mechanic so if the heater core is leaking on the passenger side would it smell like antifreeze?
I took the lower panel out and lifted up the carpet. It is all wet under passenger side. Coming from the fire wall. I soaked up the water in the carpet and padding

Yes you should be able to smell it and when you turn the defrost on the windshield will likely fog up.  At least mine did.

[nwmein199]

Ok had the window shop test the windows all is good. I’m not a mechanic so if the heater core is leaking on the passenger side would it smell like antifreeze?
I took the lower panel out and lifted up the carpet. It is all wet under passenger side. Coming from the fire wall. I soaked up the water in the carpet and padding

So are you saying you sealed the leak at the shark fin and you still have leaking but on the passenger side of the truck? Was it always leaking on the passenger side only?

[jstone]

The passenger side is very wet. I have it in the shop as I type

[Buckmark]

The passenger side is very wet. I have it in the shop as I type

Drill a hole in the floor, problem solved 

[Shaqdiesel]

When I had a faulty door seal on my front passenger side, we found it with one person inside the truck and the other spraying a hose on the roof. I had discovered a wet floor when vacuuming the truck under the floor mat and went from there. 2011 Sierra

[High Climber]

Those trucks are notorious for leaking from the OnStar antenna...

[Black Ghost]

I had dealership fix and reseal the original sharkfin twice.  Each time the problem returned within a year.  I just had the dealership replace the shark fin with new design.  GM takes little to no ownership for this problem. I have the 2015 duramax 3500 and water was pooling on passenger floor board, lost all navigation feature.  I am satisfied this time it is fixed., but time will tell. The small gap that was  in back of the original fin is now replaced with a solid gasket seal.  Dealership charged me $550 for replacement and installation.  Any silicone temp fix will not have long lasting impact, replace it and save yourself the future headaches.  I feel your pain, love this truck but cant believe they dont do a recall and fix this problem without putting the financial responsibility to loyal customers.

[jstone]

The shop looked at my truck. Not the heater core. He said water is getting in somewhere in the seam in the firewall? Told me to take it to a body shop and have them take the fender off and look at the seam. There was some pine needles in the dash. This crap is driving me nuts.!!
I have the carpet up and drying it out during the nice weather