2018 Sierra 3500 Leaking....driver side floor SOAKED.

[Jody Davis]

Good evening,

 

I havent driven my 2018 Sierra 3500 much lately because we aren't in camping season but i noticed tonight that the windows were super fogged up badly.  I opened the truck up and the drivers side front and back is seat is SOAKED.  I pulled the factory "premium" mats out. The carpet is inundated on just the drivers side, the passenger side is bone dry.  I pulled the trim piece that seperates the carpet from the door jamb on the front and back seat floor and in the back seat you could see standing water underneath it.  when i changed my trucks angle from the bed going downhill slightly to the nose going downhill slightly all the water moved from the back up to the front and pooled by the gas peddle.  This truck was bought brand new last year and only has 10k on it.  I will take it to the dealer tomorrow but just wondering if anyone has had this happen before. I checked the shark fin and it seems pretty tight, if i force it i can see the seal lift a little.  Nothing was super obvious. Thanks!

[Cootr68]

My 15 did same thing. Turned out to be the shark fin gasket and instead of replacing it I put some clear silicone around it. Solved the leak and can't tell it's been siliconed.