Water leak. Standing water in drivers floorboard

zrlee · June 5, 2016

I have a 2016 crew cab Silverado ltz z71.

We've had 2 nights in the past week with lots of hard rain. The morning after the first big rain I had quite a bit of water standing in the drivers side floor mat. That morning I took it directly to the dealership while it was still wet. Looks to be coming from under the drivers side dash. I asked them to check the firewall seals and sunroof. They checked the sunroof drains and replaced the onstar antenna seal. The next day we had more rain and again the next morning I had water in the floorboard. I decided to dive in and see what I could find. I removed both pilar handles and nothing was wet. I took buckets of water and dumped on my sunroof and windshield and around the antenna. Even tried pouring water by the wipers and could not get it to leak. When I look up under the dash I can see that water has dropped on everything but can't find the source.

Any help or ideas would be appreciated!

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Colossus · June 6, 2016

Only thing I can think of is windshield seal not done properly at the factory.. I don't know.. But I'd take it back to the dealership again, you need to keep this recorded and addressed ASAP.

TxTruckMan · June 6, 2016

I had the same problem in my 2014 Denali. It was leaking at the top of the windshield and then travelling down the A pillar and then through the dash onto the floor. Sometimes it would soak the headliner depending on how I was parked. It could also be your sunroof or the OnStar antenna, but most likely your window.

zrlee · June 6, 2016

Everything from the dash up is completely dry. Including behind the handles on the A pillars and the headliner. They've replaced the onstar seal already and sunroof drains are working properly and still leaks. My bet is on the windshield but the dealership has had it all day. I would imagine that would be the first thing they checked but still no word. We'll see.

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GMCustomerService · June 7, 2016

Good morning zrlee,

I’m sorry you’re experiencing a mysterious leak in the driver’s side of your Silverado, but I’m happy to see you’re working with a dealership to get this concern diagnosed. I would be happy to offer my assistance when working with your dealership. Please send me a private message at any time if you would like to discuss this situation further.

Best,

Julianne M.

GM Customer Care

Everything from the dash up is completely dry. Including behind the handles on the A pillars and the headliner. They've replaced the onstar seal already and sunroof drains are working properly and still leaks. My bet is on the windshield but the dealership has had it all day. I would imagine that would be the first thing they checked but still no word. We'll see.

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Old School Mechanic · June 8, 2016

We had the same problem with our 2013 Sierra at work. Everything dry except the floor board.

New windshield seal fixed it.

ikaika1984 · June 9, 2016

I have a 2016 crew cab Silverado ltz z71.

We've had 2 nights in the past week with lots of hard rain. The morning after the first big rain I had quite a bit of water standing in the drivers side floor mat. That morning I took it directly to the dealership while it was still wet. Looks to be coming from under the drivers side dash. I asked them to check the firewall seals and sunroof. They checked the sunroof drains and replaced the onstar antenna seal. The next day we had more rain and again the next morning I had water in the floorboard. I decided to dive in and see what I could find. I removed both pilar handles and nothing was wet. I took buckets of water and dumped on my sunroof and windshield and around the antenna. Even tried pouring water by the wipers and could not get it to leak. When I look up under the dash I can see that water has dropped on everything but can't find the source.

Any help or ideas would be appreciated!

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Do you have a GPS antenna, if so your seal might have gone bad.. Mine did, and water ran down the A pillar into floor board

Sent from my SGS7

ikaika1984 · June 9, 2016

Do you have a GPS antenna, if so your seal might have gone bad.. Mine did, and water ran down the A pillar into floor board

Sent from my SGS7

Sorry late reply, seen your message about antenna...

Sent from my SGS7

20feetup · June 13, 2016

Was the source determined here ?

LaserBlueZ71 · June 14, 2016

I know it has been mentioned, but just to let others know how common this is, my onstar antenna leaked badly within a month of picking up my 2015.

Soaked my headliner and it ran down the A-Pillar to the floorboard. My advice to anyone with any kind of issue, especially water intrusion, document every single thing. Take all the pictures in the world so that the corporate monster cannot argue with you. Proof is your best friend.

pm26 · June 14, 2016

It appears that the design of the antenna base gasket requires that it be securely tightened against the roof. Apparently some of these antennas bolts are left rather loose at the factory, resulting in water leaks. Looks like they need to take a harder look at their quality control wherever they assemble these trucks. And as mentioned, there are other sources of leaks, like faulty windshield seals, which again can be tied to lousy workmanship and insufficient quality control.

Edited June 14, 2016 by pm26

kylercochran361 · June 14, 2016

Good morning zrlee,

I’m sorry you’re experiencing a mysterious leak in the driver’s side of your Silverado, but I’m happy to see you’re working with a dealership to get this concern diagnosed. I would be happy to offer my assistance when working with your dealership. Please send me a private message at any time if you would like to discuss this situation further.

Best,

Julianne M.

GM Customer Care

Customer service needs to stay out of these threads. All they do is talk but nothing is done about shit. My 2015 Sierra was shifting gears super hard over and over. Literally would make the truck come to a sudden stop or seem like it jump a whole gear. And the only thing your piece of shit service did was recommend going to get it checked. Of course this is how it works as in when I take it in all a sudden it doesn't happen. Or at least that is what they tell me. Don't feel like paying $55000 for a truck that has problems and won't be fixed. Of course of GM is about is their damn money. Will be definitely looking into a different brand truck next go around forsure on that has better customer service. You guys should believe the customer for once instead of not doing anything about the situation and my truck crapping out at 100k then GM reply sorry it's past your warranty. This is how I finally realized GM works. Thanks for selling me a $55k lemon.

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TxTruckMan · June 14, 2016

Customer service needs to stay out of these threads. All they do is talk but nothing is done about shit. My 2015 Sierra was shifting gears super hard over and over. Literally would make the truck come to a sudden stop or seem like it jump a whole gear. And the only thing your piece of shit service did was recommend going to get it checked. Of course this is how it works as in when I take it in all a sudden it doesn't happen. Or at least that is what they tell me. Don't feel like paying $55000 for a truck that has problems and won't be fixed. Of course of GM is about is their damn money. Will be definitely looking into a different brand truck next go around forsure on that has better customer service. You guys should believe the customer for once instead of not doing anything about the situation and my truck crapping out at 100k then GM reply sorry it's past your warranty. This is how I finally realized GM works. Thanks for selling me a $55k lemon.

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What else do you expect from them? To fix your truck over the internet? WTF?

They're here to help. Some people need different help than others (obviously). Let them be.

kylercochran361 · June 14, 2016

What else do you expect from them? To fix your truck over the internet? WTF?

They're here to help. Some people need different help than others (obviously). Let them be.

You even know what you are talking about? I said I worked with them over email and over the phone. You get the same message every time. And it's just the same thing over and over. So do me a favor and don't come in unless you know what I'm talking about. I am bashing them cause they come on to these forums to save there ass when it's bull. Go to their profile and take a look at their replies it is literally repetitive. Anyways have a good day.

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TxTruckMan · June 14, 2016

You even know what you are talking about? I said I worked with them over email and over the phone. You get the same message every time. And it's just the same thing over and over. So do me a favor and don't come in unless you know what I'm talking about. I am bashing them cause they come on to these forums to save there ass when it's bull. Go to their profile and take a look at their replies it is literally repetitive. Anyways have a good day.

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I'm sorry that my simple question was so difficult for you to answer.

I'm here to help the OP. You're here to bitch about GMCS reps that are just doing their job and also trying to help. You're the one that needs to leave. Nobody wants to hear about your problems. And FYI, I can bet that YOU are part of your problem.