RamPart3.9
Junior Member
Having owned my 2015 Ram 1500 for 5+ years now with no issues I started noticing my windows being fogged up in the mornings and a slight musty smell. This was getting progressively worse when one day I raised my rear seat and discovered my storage compartments were 1/4 full of standing water. My immediate thoughts were rear side window/door seals leaking or not fully closed when raining but after a water hose test that was not the case. My Ram does not have a rear sliding window so ruled that out as well. Reaching under the rear seat all the way to the back wall I could feel water there as well.
I had heard about the Third Brake Light Leaks so decided to check that with a water hose and discovered fresh water coming in at the rear of the headliner on the right and left sides near the rear posts/seat belts behind the doors. I pulled the Third Brake Light and discovered the foam seal to be completely collapsed and old looking. I ordered an oversized replacement seal for it and after replacing it and running a water hose test did not have any water coming in as I had previously discovered at the headliner rear posts/seat belts.
Thinking all was good and having dried the carpet/padding under my rear seat I quit looking for leaks. Not long after the Third Brake Light Seal replacement we had a 2+ inch monsoon rainstorm. After it was over I went out to my truck and noticed the windows were fogged on the inside once again. I immediately thought it was the Third Brake Light Seal once again but upon inspection all was dry in the headliner and rear posts. I raised the rear seat and once again I had 2-3 inches of standing water in the storage compartments.
After doing a little research I learned about "Rear Cabin Vents" failing and allowing water to enter the interior behind/under the rear seat. I removed my rear seat and all the padding/carpet under/behind it. The amount of dampness was incredible. Upon inspecting the Rear Cabin Vents I discovered them to have both failed and missing multiple flaps allowing you to see outside and the front of the truck bed.
I ran a water hose on top of the truck cab and as the water ran down the rear window and down the back of the cab it was pouring in/around the two Cabin Vents like the "Titanic after striking the iceberg"... I pulled the vents and discovered even worse deterioration and failure. The outer seals were hard and split in multiple places, and the remaining vents flopped in the openings without being firmly seated. With the Vents removed I decided to tape a piece of clear plastic over the opening to show the amount of water flowing down and over the Vent area. I cannot believe that there is not any type of a shield/cover above the outside vent areas to divert water from these areas? A simple awning would go a long way in preventing water from entering the cab when or if the vent failed. Of course a better made vent is needed to completely seal the cabin from both water and dust.
To end this frustration release, I have ordered replacement Cabin Vents that are supposedly improved to prevent this from happening again. They have yet to arrive but once they do I will install and run a test. I have temporarily taped both Vent Openings up until I have the new Cabin Vents and will have to crack a window when closing doors or running the a/c or heater. I have not re-installed my rear seat, padding or carpet. Follow-up report to be posted after installation and test. Fingers Crossed.
View attachment 239183
I had heard about the Third Brake Light Leaks so decided to check that with a water hose and discovered fresh water coming in at the rear of the headliner on the right and left sides near the rear posts/seat belts behind the doors. I pulled the Third Brake Light and discovered the foam seal to be completely collapsed and old looking. I ordered an oversized replacement seal for it and after replacing it and running a water hose test did not have any water coming in as I had previously discovered at the headliner rear posts/seat belts.
Thinking all was good and having dried the carpet/padding under my rear seat I quit looking for leaks. Not long after the Third Brake Light Seal replacement we had a 2+ inch monsoon rainstorm. After it was over I went out to my truck and noticed the windows were fogged on the inside once again. I immediately thought it was the Third Brake Light Seal once again but upon inspection all was dry in the headliner and rear posts. I raised the rear seat and once again I had 2-3 inches of standing water in the storage compartments.
After doing a little research I learned about "Rear Cabin Vents" failing and allowing water to enter the interior behind/under the rear seat. I removed my rear seat and all the padding/carpet under/behind it. The amount of dampness was incredible. Upon inspecting the Rear Cabin Vents I discovered them to have both failed and missing multiple flaps allowing you to see outside and the front of the truck bed.
I ran a water hose on top of the truck cab and as the water ran down the rear window and down the back of the cab it was pouring in/around the two Cabin Vents like the "Titanic after striking the iceberg"... I pulled the vents and discovered even worse deterioration and failure. The outer seals were hard and split in multiple places, and the remaining vents flopped in the openings without being firmly seated. With the Vents removed I decided to tape a piece of clear plastic over the opening to show the amount of water flowing down and over the Vent area. I cannot believe that there is not any type of a shield/cover above the outside vent areas to divert water from these areas? A simple awning would go a long way in preventing water from entering the cab when or if the vent failed. Of course a better made vent is needed to completely seal the cabin from both water and dust.
To end this frustration release, I have ordered replacement Cabin Vents that are supposedly improved to prevent this from happening again. They have yet to arrive but once they do I will install and run a test. I have temporarily taped both Vent Openings up until I have the new Cabin Vents and will have to crack a window when closing doors or running the a/c or heater. I have not re-installed my rear seat, padding or carpet. Follow-up report to be posted after installation and test. Fingers Crossed.
View attachment 239183
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