Water leaks under the dash

Tony Alberts · February 9, 2015

I recently purchased a 2015 Chevy Silverado. The other day during heavy rain getting into the truck after it sat for awhile I noticed the interior windows were all fogged up. Didn't think anything about it, just turned on the AC for a bit to dry out the interior and the problem cleared up.

The next day again after a heavy rain I noticed about a cup of water on the driver side floor mat. The windows had been rolled up the doors fully closed. I noticed drops of water on the e-brake pedal, it appears the truck was leaking from somewhere under the dash.

I will be contacting the dealer on Monday but I'm curious if anyone else has noticed this problem.

I don't want my new truck to develope electrical issues or to start smelling moldy from a wet carpet.

POS VETT · February 9, 2015

I can almost bet money the water came through the leak at the multi-band antenna on the roof.

BuddyS · February 9, 2015

I recently purchased a 2015 Chevy Silverado. The other day during heavy rain getting into the truck after it sat for awhile I noticed the interior windows were all fogged up. Didn't think anything about it, just turned on the AC for a bit to dry out the interior and the problem cleared up.

The next day again after a heavy rain I noticed about a cup of water on the driver side floor mat. The windows had been rolled up the doors fully closed. I noticed drops of water on the e-brake pedal, it appears the truck was leaking from somewhere under the dash.

I will be contacting the dealer on Monday but I'm curious if anyone else has noticed this problem.

I don't want my new truck to develope electrical issues or to start smelling moldy from a wet carpet.

I can almost bet money the water came through the leak at the multi-band antenna on the roof.

I double what POS VETT said

Check this thread out: http://www.gm-trucks.com/forums/topic/158522-water-leak-in-the-roof/

I have been wondering if any 2015 would leak

Have you noticed the leak after a freeze?

BuddyS · February 9, 2015

Hello GM, but are we all going to have a stinky mildewed truck in a years time or will you decide to come out with an official fix for this and not a dealer patch with RTV??????

We are talking about ~$50k tuck and a ~$45 dallor part, really? I mean if it was designed correctly you can sell the part cheaper, R&D payback.

rocnrol · February 9, 2015

My two cents on this...... i had the exact same leak.... would get into the truck to see water in the floor mat, but the roof and pillars were dry. turned out to be grommet out of place on the fire wall. Haven't had a leak since.

pm26 · February 9, 2015

My two cents on this...... i had the exact same leak.... would get into the truck to see water in the floor mat, but the roof and pillars were dry. turned out to be grommet out of place on the fire wall. Haven't had a leak since.

You are describing exactly what I experienced with my old 1985 Mercedes 300D. It leaked only once after a heavy rain, and it turned out to be a displaced hood release cable grommet on the firewall. When I sprayed some water on the windshield, I could see it dripping from the front cowl onto the grommet and flow into the grommet hole. After I pushed the grommet fully into place, no more water leaks. Sometimes it is the simplest problem that can be fixed in a minute or less.

Edited February 9, 2015 by pm26

scott19677 · February 9, 2015

Yes you will get mold. My 2007 had this problem. It took a few years to rear its ugly head. MOLD IS VERY DANGEROUS!!. I am very sensitive due to having Asthma. Kept getting cold symptoms. Never smelled anything for about two years. The dealer had to strip everything out. Then I traded it in. Im just saying do not take it lightly. Good luck.

BuddyS · February 15, 2015

I recently purchased a 2015 Chevy Silverado. The other day during heavy rain getting into the truck after it sat for awhile I noticed the interior windows were all fogged up. Didn't think anything about it, just turned on the AC for a bit to dry out the interior and the problem cleared up.

The next day again after a heavy rain I noticed about a cup of water on the driver side floor mat. The windows had been rolled up the doors fully closed. I noticed drops of water on the e-brake pedal, it appears the truck was leaking from somewhere under the dash.

I will be contacting the dealer on Monday but I'm curious if anyone else has noticed this problem.

I don't want my new truck to develope electrical issues or to start smelling moldy from a wet carpet.

Hi, I am curious if you have found out for sure where your leak is coming from. I have noticed that the 2015 models have a larger antenna as the 2014, may have something to do with the new onstar/wifi band???

So, I am wondering if these antennas leak as well.

Z71 Blackout · March 16, 2015

I purchased my new 2015 Silverado crew cab a month ago and has not been the best experience starting with the dealer the truck came from must have had a midget clean the snow off the roof with the snow rake leaving 15 yes 15 dents in the roof. Next off today went to vacuume out the truck and saw a puddle of water on the pass side against the kick panel. I took off all the trim and pulled back the carpet to reveal sm puddles under the carpet and insulation and the foam piece under the glove box. I am beside myself right now. This truck was $48,500 and this is what I get. It has just over 1k miles and have owned it for a month. This is my 7 th new Gm and will probably be my last.. Going to the dealer tomorrow can't wait to see what they say.

pm26 · March 16, 2015

Hi, I am curious if you have found out for sure where your leak is coming from. I have noticed that the 2015 models have a larger antenna as the 2014, may have something to do with the new onstar/wifi band???

So, I am wondering if these antennas leak as well.

Who knows.

Z71 Blackout · March 16, 2015

My two cents on this...... i had the exact same leak.... would get into the truck to see water in the floor mat, but the roof and pillars were dry. turned out to be grommet out of place on the fire wall. Haven't had a leak since.

I hope it's that easy. It's at the dealer now.

rocnrol · March 17, 2015

I hope it's that easy. It's at the dealer now.

Good luck!

20Denali22 · March 18, 2015

I can almost bet money the water came through the leak at the multi-band antenna on the roof.

+1

Z71 Blackout · March 20, 2015

So here's a update. Under ther cowl there is a water diverter piece. Well on all the welds on the truck they use seem sealer. On the weld by this piece the seem sealer was put on and a extra piece remained as the robot or human that applies the seem sealer and stopped the application extra leaked out and was left on the cowl where the water diverter lays flush. Well because of the extra sealer under the water diverter it was not flush and the water ran under the diverter and down the firewall and in though where the wiring harness is on the passanger side. The had to move the fender out of the way to repair it correctly. The removed the extra sealer and made the water diverter flush then sealed the water diverter and re assembled what they removed. No more leaks and they dries out the carpet and insulation stuff and I get to pick it up tomorrow. We shall see how they did when I inspect it tomorrow. Thanks for the replies.

Collimare · May 10, 2015

I also have a less than two week old 2015 2500HD Duramax LTZ Crew Short (last 8 of the VIN: FF558385). It has been raining the last two days here in Golden, CO so I pull the truck into the shop to install the new weather tech floor mats only to find standing water in the passenger floor board when removing the factory rubber mat. I jump in the truck and immediately take it to the dealer who vacuumed the water out and I left it airing out at the dealership. Hopefully they will find the problem quickly on Monday. I simply cannot believe it and am beyond disappointed!!!

I wonder how many more are out there with the same issue? I am just glad I found mine this quickly. With normal Colorado weather it could have gone undetected for a very long time had it not been for the steady rain and changing the floor mats. I would never ever think I needed to check the carpets for water. Guess I'll check every rain now.

Is there an official service bulletin yet?