Cab retaining water, common problem areas?

[baglie1]

I have a 2012 GMC Sierra 1500 Crew Cab 4WD and a few severe storms recently passed through with very heavy rainfall and winds. Now, when I drive, I heard fluid/water sloshing around!!! The bed is dry :-(. Are the 3rd Brake Lights an issue with these trucks? I've only had the vehicle for a few months and have barely driven, so I'm still not that familiar lol. In my mind the obvious are the rear windshield and the 3rd brake light gasket...

[richard wysong]

You are probably hearing water in the doors, make sure the drain holes are clear

[nitrozamboni]

It’s probably water in the doors. Mine had tape over the drain holes! Poked them open and that took care of it. Now I’m waiting for the rust to come through!

[Z45]

Dirt settles in the door drain holes and traps water....lower corners of inside door skin.  

[Homer1959]

On 6/12/2026 at 8:51 PM, baglie1 said:

I have a 2012 GMC Sierra 1500 Crew Cab 4WD and a few severe storms recently passed through with very heavy rainfall and winds. Now, when I drive, I heard fluid/water sloshing around!!! The bed is dry :-(. Are the 3rd Brake Lights an issue with these trucks? I've only had the vehicle for a few months and have barely driven, so I'm still not that familiar lol. In my mind the obvious are the rear windshield and the 3rd brake light gasket...

Thanks for not getting back to share your findings...  

[baglie1]

ha!!! Sorry, I completely forgot I posted this, got crazy busy with family passing. Yes, a door retained a bunch of water after a bad storm! Again, sorry! Life

 

nitrozamboni, tape over the drain holes? Why, just why, would somebody do that lol...crazy!

Edited 1 hour ago by baglie1