2015 Tahoe/I hear water

[MrMacaroni]

When sitting in traffic, I can hear the sound of water gurgling near/behind the dash in our 2015 Tahoe. Please advise.

 

[Bill 1960]

Air in the coolant. Either a leak, or a blown head gasket if your luck is bad.

 

[GreyStone]

This is for 21s but may still apply to sunroof drains??https://gm-techlink.com/?p=14229#:~:text=There may be a gurgle,left sunroof drain hose areas.

 

[Gmfm]

I’ve had this happen on my Sierra. Going on your information you may have an air pocket in your heater core. Try this. Have the engine off and cold
Make sure coolant is at the proper level.
Open the cap on the reservoir tank.

Start the vehicle with the coolant cap off.

Wait for the engine to warm all the way up 10-15 minutes. At least enough for the thermostat to open. The air will purge from the system.
Put the cap back on and drive around and see if the problem is resolved. Make sure to check your coolant level Again when the engine has fully cooled.