Inside of front windshield frosted over.

[Huffy2346]

Good morning,

I live in the Pacific Northwest where the last couple days have been in the teens to the single digits for a low temperature… I went out to my truck and noticed frost on the inside of the windshield… I drive the truck sometimes 2-3 times a week and sometimes it sits 2-3 weeks before driving it… Called the dealer, and they say this is common for this time of year, especially when it gets as cold as it’s been… They also said there’s nothing they can do… I have owned a lot of vehicles in the past, and I feel like I’ve never had this issue before… Is anyone else having this issue? Is this a common issue?And if so, is there a fix? My truck is a 2022 Ram 1500 Limited… Thanks

 

[Curmudgeon]

Buy some of these, hang one in your truck? I tried it once when I discovered I left a window down part way, then it rained. I think it took maybe 12 to 36 hours, I don't remember, but it got all the moisture, even dried the carpet.

Frost or ice on the inside of your windows is coming from relatively high moisture/vapor inside your truck. Look around very thoroughly and carefully for any leaks, signs of water stains, dampness or wetness you can feel, etc.

Good luck!

EDIT: https://www.amazon.com/DampRid-Fres...05597295&sprefix=damp+rid,aps,172&sr=8-6&th=1

 

[Daw14]

I bet you have water intrusion somewhere, it’s raised the humidity in the cab . Now it’s frosting over when the temp drop. Search this forum for possible leak areas , there’s plenty.

 

[OC455]

What they said ^^^

 

[Musky Mike]

Do a search, there have been some problems on here before. There are some vents behind the rear seat that could be the problem.

 

[chopperman1]

Dealership is full of crap! You have a water leak somewhere, most likely your 3rd brake light. Next 2 most common areas are your cab vents (behind rear seat) or your back window frame cracked.

 

[Huffy2346]

I will start paying attention to the brake light and see if I see any water coming out of that…I have heard the rear vents may be causing the problem a couple of times…Is that something I can close the vents or do they need to be replaced?

 

[canadiankodiak700]

As much hate as I have on the dealerships, they are not 100% wrong. This is very common at this time of year and through it the winter. There are several things that you can do to help eliminate this issue. A few questions first though. First of all, do you eat fast food in your vehicle or drink coffee often in there? There's a very good chance that your windshield is actually covered with a little bit of grease from the steam from your food and your coffee. As that steam condenses on your windshield, the thin film of grease and oil Will actually cause little pockets that doesn't allow moisture to run or evaporate as well as it should on a very clean windshield. Often the bottom of your windshield doesn't get cleaned as well as the rest because it's further out and down low in an area that's kind of hard to reach easily. Another question, are your floor mats filled with water , ice, or slush? Your floor mats are one of your biggest contributors to moisture inside of the vehicle that most people don't think of. Also, another thing to be sure of is when you're running your heater, make sure your AC button is turned on. It's not going to act as an air conditioning. It's going to act as a dehumidifier which will take out the moisture. It should be doing this automatically when in defrost mode but doesn't always work as well as ensuring that the AC is actually turned on.

 

[Dean2]

Make sure you don't have your air set to recirculate. That is the single biggest cause of frosted windows. Last week it was -40 here. Saw a ton of vehicles with heavily frosted windows inside. All being driven by immigrants. They think recirc heats faster than heating outside air. All it does is load damp air from inside and freeze it to the windows inside. If you are on full defrost, it does it even faster.

 

[CanRebel]

I have van that does that, and have different cars over the years do it as well. You should check the places the people above mentioned. But that is not always the cause.
Van does it cause my Wife drives it. Kids bring in lots of snow, she turns the temp to 40c , in the morning there is frost on windshield.
She puts cat litter, instead of telling kids to clean off snow before getting in.

@Dean2 mentioned a good example(s).

But there are others. door seals as example, which aren't causing water leaks.

 

[Daw14]

Vents are available for under $10.00 , change the third brake light gasket with hardware store weatherstripping.

 

[G Allen]

I will start paying attention to the brake light and see if I see any water coming out of that…I have heard the rear vents may be causing the problem a couple of times…Is that something I can close the vents or do they need to be replaced?

You need those vents. I read once where someone closed them off with duct tape and then both doors got closed at once and blew out the back window. The vents are only about ten Bucks each and you can do it yourself. I did. I had the one on the passenger side leaking. check under the back seat (if you have one) for moisture. You can change them out from within the vehicle vs outside where you need to move the truck box rearward. YouTube vid:

Ram 1500 cab vent water leak fix

Ram 1500 rear cab vents leaking water into the truck.@$18 for both vents purchased from dealer.Problem solved.

youtu.be

 

[yroyerr]

I also live in the Northwest and had that problem on my 2012 Ram 3500 Laramie. Water was accumulating in the storage area under the rear seat and making the truck very humid inside. There were 3 areas where water was coming in during rain and none of them were the brake light.

One was the moonroof. The seal there is not a complete seal and there are drain paths on the four corners below the moonroof. I never leave the moonroof open under a tree sine.then.

The second was the cab vents behind the rear seats. Seats have to be removed to access them. I used silicone to seal all around them after drying them out.

The third one is difficult to explain (sorry, I don’t have photos). You need to look at it from the outside in the truck loading area directly behind the rear sliding window if you have one. On the inside there is a sliding track and a drain track; you see the drain holes on the outside and they can get plugged. In my case, too much water was coming in and overwhelming the drain track during one of those atmospheric rivers. From outside, look at the seal in the bottom do the sliding window; this is a piece of rubber inserted between the vertical seals on both sides. Over time, this part will shrink and you will horizontal openings where it meets the vertical seals. Right under these openings is the inside drain track. Seal these openings as the water tends to run around the brake light and is routed directly over these openings during rain. It’s a good time to inspect the brake light too.

What’s left are window seals and an Opening under the top rain track due to a poor weld in the body there. By the way, unless I switch the vent to recirculating before truing off the truck for more than a day, my front windshield always get misty on startup after rain. It takes a long time for that Cummins to heat up.

Good luck!

Yvon Royer
2012 RAM 3500 Laramie
6.7 L Cummins 68RFE

 

[TRK_GANG74]

I had the same problem with my windshield frosting over from the inside. I thought it was the gasket around the windshield but it wasn’t. It turned out to be the sunroof drain on the rear drivers where it exits the rear of the cab. It wasn’t seated properly where it exited the cab body and it was enough to allow water to enter and make its way up to the drivers footwell via the door sill trackway. Apparently it had been that way since the truck left the factory. Had a tech at the dealer seat the sunroof drain plug and I replaced the 3rd brake light gasket and added some flowable silicone to the outside edge of the gasket. No more leaks in the last 3 months! Check where your rear sunroof drains exit the cab body between the bed and rear cab wall.

 

[GjwRI]

2016 1500 Laramie Longhorn. I live in Rhode Island. We had a rainstorm that turned to snow that turned to a more frigid cold snap (teens and 20's high temps) recently, and same thing happened to my truck, inside front window frosted over in the morning. I have a sunroof, and I observed water dripping from a section of the headliner and driver side grab handle (in windshield pillar) screw plug. These pillars are where the sunroof drain tubes run, and empty very close to the front door hinges where they attach the door to the body. These drain fixtures were iced over and shut, preventing sunroof drain water from dripping out, and therefore backing up into cabin onto carpet, and resulting in frosted interior windshield. I removed the ice with my fingers, water dripped/flowed out, and interior cabin is slowly returning to a more normal humidity.

 

[Huffy2346]

Thanks everyone for the advice!! I really appreciate it!! I will start to look at all those areas and see what I can find….Everyone take care and have a great day!!

 

[inuyasha-rules]

Mine does this if it's below -20 and I've been doing short trips not getting the cab warmed up. Setting it to defrost and not full hot (about 80%) helps pull the moisture out of the air for me. Last week it hit -39 and our work van didn't warm up at all - I left it run/drove short trips for 5 hours and it barely made it above cold and frosted up pretty bad inside.

 

[GTyankee]

run the Heat, but only about 75 - 80 percent flow, then after a few minutes, turn on your Defroster.

As someone mentioned, clean the inside of the windshield

I don't know for sure, but i keep a small bag of bamboo charcoal on my dashboard in the center, against the windshield, i think it draws the moisture off & cigarette smoke too

Bamboo Charcoal Air Purifying Bag with Odor Control,​

Walmart, Home Depot, Lowes
$2.00 - 3.99, depends where you shop




reuse for about 2 years, put it in direct sunlight to reactivate it, every month or so

 

[Fatbob Frank]

Mine will do that if I have the HVAC on recirculating mode...
Humidity inside the cab (brought in on shoes usually) blows out the vents and freezes to the cold windshield.
It will usually start to fog over the side windows too...
One thing I've come to appreciate is my PW warms up much faster than my 1500 Laramie did.
When it's -20 out my Laramie would take half way to work before it stated getting warm air out of the vents.
My PW does it within the first mile or 2...

 

[Huffy2346]

Quick update!!

So we had a pretty good rain fall this afternoon and I happen to be driving the truck. I was waiting for my kids to come out of school so I started to look around for any leaks.

I started with feeling around the sun roof area and didn’t feel anything wet. As I looked at the back window on the passenger side of the truck, I noticed a small stream of water running down the window on the inside. After taking a video of the leak and dropping my kids off at home, I took the truck back to the dealer.

I talked to one of the service guys, someone I haven’t dealt with before and showed them the video I took of the water leak. He proceeded to tell me they have a known issue of the rear glass having cracks in them coming from the factory in Ram trucks from years 2019-2024.

I was not very happy. They didn’t even try or even want to look at my truck before I showed them the video of the leak. They continued to brush me off, even after knowing there was a known issue coming from the factory.

They have now ordered a new back window for my truck. It should be here in a couple of weeks. Hopefully that will fix the issue of all the condensation inside the cab of the truck. Thanks again for all the advice. Take care!!