Driver B Pillar wetness during torrential downpour

[TheGrrrrr]

On the way back from LCDC I encountered the hardest rain I have ever seen. It was bad enough that I had to pull over because visibility was down to zero. About 15 minutes into the storm I noticed the upper B Pillar inside the truck was damp and getting wetter. After the rain subsided it dried up pretty quickly. The door seals appear to be fine, so I'm guessing its coming in from the roof rack mount points. before I tear apart my roof rack to try and reseal, is there any other possibility I should be thinking about?

The wetness is definitely starting at the top of the pillar and working its way down.

 

[rusty87]

Sun roof drains?

 

[CharlieS]

Sunroof drains are my guess as well.

 

[Lexzilla]

I had the same. Took me several tries to chase it down. Ended up being a leak in seal at the top of my windshield.

 

[RobW0]

I would probably start with the sunroof and then look at the rack. Would not be surprised if it was the rack. Did you make to Black Bear on the way home?

 

[TheGrrrrr]

I would probably start with the sunroof and then look at the rack. Would not be surprised if it was the rack. Did you make to Black Bear on the way home?

I didn't make Black Bear. HVAC issues at the house resulted in a race home Sunday morning. Made it from Ft. Collins to Scottsdale in 12:45 which was really pushing it. The dog was not happy that the house was 97 degrees, but he survived.

 

[RobW0]

I didn't make Black Bear. HVAC issues at the house resulted in a race home Sunday morning. Made it from Ft. Collins to Scottsdale in 12:45 which was really pushing it. The dog was not happy that the house was 97 degrees, but he survived.

Sorry you did not get to run Black Bear, even more sorry to hear about your HVAC problem.

 

[bloc]

Were you parked on a side hill? Wetness on both sides, or only the downhill one if side hill?

The sunroof drains only work well if the vehicle is somewhat level. If the gasket has shrunk letting more water in than when new, and tilted to one side, you can overwhelm the drains pretty easily. The front ones are easy to test, the rear are buried pretty far back so it’s hard to actually see them empty. And IIRC they exit out the drains along the rocker panel, so it can be hard to verify where it’s coming from.

And before you potentially make the mistake, be very careful if you use compressed air to clear the drains you can get to. It can pop the drain line off the nipple on the bottom of the sunroof tray, which is a major headache to fix.

 

[TheGrrrrr]

Were you parked on a side hill? Wetness on both sides, or only the downhill one if side hill?

The sunroof drains only work well if the vehicle is somewhat level. If the gasket has shrunk letting more water in than when new, and tilted to one side, you can overwhelm the drains pretty easily. The front ones are easy to test, the rear are buried pretty far back so it’s hard to actually see them empty. And IIRC they exit out the drains along the rocker panel, so it can be hard to verify where it’s coming from.

And before you potentially make the mistake, be very careful if you use compressed air to clear the drains you can get to. It can pop the drain line off the nipple on the bottom of the sunroof tray, which is a major headache to fix.

I noticed it before I stopped, so it was getting in while I was driving down I-25, not just stationary. Do the sunroof drains run anywhere near the top of the B pillar?

 

[bloc]

I noticed it before I stopped, so it was getting in while I was driving down I-25, not just stationary. Do the sunroof drains run anywhere near the top of the B pillar?

I haven’t dropped my headliner but on most vehicles the drains are at the outer corners of the pan, and that is usually much closer to the C pillar.
Now if the pan overflowed out the side it could be in the middle near the B pillar, but we’d have to have a look where he low spots are. Also keep in mind if the pan overflowed to the inside hole, that you look up through, as opposed to the outer edge, the headliner would likely then catch it and flow to the low spots. B pillar could be path of least resistance there.

 

[Artie]

This may be a dumb question but how do the window seals and whatever other rubber stuff keep a good seal when these vehicles are taken off road and subjected to lots of body and frame flexing?

 

[bloc]

This may be a dumb question but how do the window seals and whatever other rubber stuff keep a good seal when these vehicles are taken off road and subjected to lots of body and frame flexing?

The frame being isolated from the body helps the body avoid some of the flexing the frame does off-road, also these bodies and doors and structures are quite stiff.. but if you look at the door seals they are bigger than strictly needed to account for some movement. Also things like the sunroof assembly, where you can’t reasonably seal it water tight, it has a system of what amount to gutters to collect the water that does make it through and safely discharge it where it shouldn’t hurt anything.