2019 Silverado Z71 Crew Cab - 37K miles - Mildew Smell

[kyfisherman1]

I have a 2019 Silverado Z71 Crew Cab with 37K miles.  I started smelling a mildew smell roughly 6 months ago (maybe 5K miles back) and I thought it was from some wet boots I left in my truck and it was a very light smell.  However,  the smell has gotten progressively worse and I can't find any moisture, wet spots or actual mildew that is visible in the truck.  During the last cold snap here in KY I did find a spot in the back corner of the rear window where there was some water actually frozen on the inside corner of the window (I took pics to show my Chevy dealership).  I tried to put the rear seats down to see if I could see any signs of mildew behind the seats but I guess my seats don't fold down.

The smell only seems to last for about 10 seconds when you first open the doors and get in and it seems to be the strongest when you open the back door on the driver side but when I smell the carpets and smells around the seats in that area I smell nothing after the initial shock of opening the doors and smelling it.  I have an appointment with the dealership to have my transmission looked at for the 8th time (I'm at 37K miles) and I have asked them to try to determine where the mildew smell is coming from.  I have asked them it if will be covered under warranty and they don't seem very confident.  I would have to assume that a mildew smell like this doesn't happen over night and I know in fact that I started smelling it 6 months ago.  Any suggestions or thoughts?

Edited March 2, 2023 by kyfisherman1

[diyer2]

I believe a rear window leak is a common problem. Info on this site if you look.

[kyfisherman1]

Thanks Diyer

[BIGDOGx]

1 hour ago, kyfisherman1 said:

I have a 2019 Silverado Z71 Crew Cab with 37K miles.  I started smelling a mildew smell roughly 6 months ago (maybe 5K miles back) and I thought it was from some wet boots I left in my truck and it was a very light smell.  However,  the smell has gotten progressively worse and I can't find any moisture, wet spots or actual mildew that is visible in the truck.  During the last cold snap here in KY I did find a spot in the back corner of the rear window where there was some water actually frozen on the inside corner of the window (I took pics to show my Chevy dealership).  I tried to put the rear seats down to see if I could see any signs of mildew behind the seats but I guess my seats don't fold down.

The smell only seems to last for about 10 seconds when you first open the doors and get in and it seems to be the strongest when you open the back door on the driver side but when I smell the carpets and smells around the seats in that area I smell nothing after the initial shock of opening the doors and smelling it.  I have an appointment with the dealership to have my transmission looked at for the 8th time (I'm at 37K miles) and I have asked them to try to determine where the mildew smell is coming from.  I have asked them it if will be covered under warranty and they don't seem very confident.  I would have to assume that a mildew smell like this doesn't happen over night and I know in fact that I started smelling it 6 months ago.  Any suggestions or thoughts?

Does it have the rear slider window? As said above it has been an ongoing issue to tons of other forum members here and is a issue your dealership and GM know all about. Did you take this issue to your dealer before or is this the first time at 37k?

 

If you had them look at this issue before under warranty and they claimed to find nothing, you might be able to get some coverage if not the entire process covered, which is how it should be imo! This is a well known issue and i would call foul to any dealership claiming ignorance of this issue, do not allow them to perform the temp fix which was applying copious amounts of sealant to band-aid the problem, the real fix is getting the entire back glass and frame replaced.

[kyfisherman1]

Thanks for the feedback Big Dog

[Max Thomas]

What did you do to get rid of the mildew smell. Have the EXACT same issue. Got the window fixed but now stuck with a truck that smells like a musky hunting lodge. 

[KTM rider]

You can use an open box of baking soda and also charcoal made to pull orders. It helped on my 2017 GMC that had an issue.