Suburban water ingress.

[1972Blazer]

I had an '88 'Burban that the sheet metal above both rear wheels rotted away. I discovered that when I replaced the rear speakers. That was an easy fix. My '99 'Burban leaks in the right rear and sometimes under my weathertech floor mat on the front passenger floor is covered in condensation and the carpet below is wet. Haven't found that cause yet. For the right rear, so far I've: had the right rear glass removed and reinstalled. My body shop guy laughed at me when I asked him to it, but he was shocked when he removed it and discovered about 22 inches of the top rear window seal was not sealed. That reduced the water infiltration, but didn't stop it. Next, I replaced the cargo door hinges (a really unpleasant ordeal, though the doors are nice & solid again), but it still leaked, just not as bad. Next, I replaced all of the rubber weatherstripping for the cargo doors 100%. It is now much better, but still leaks!?!?!?!?! When I'm parked, the front end is higher than the rear due to the incline in front of my house and other than the car wash, water doesn't get in there at all and even the car wash now may or may not add water. I pulled back the rear carpet up to the right rear wheel tub to see what I could see. At the rear of that tub there is some rust, telling me it's been wet for a while. Last time it rained hard, this area was wet. Metal above the wheels is solid so I am baffled where the water is getting now, though there are seems that could be leaking. Need to pressure-water-test them when it gets warmer and see if I can discover the access point. Very frustrating. Oh, one of the first places I looked for the leak was the roof rack and rear brake light assembly on the roof. No water getting in there, but I did manage to spin three of the blind nuts that the roof rack screws fasten into. Another fun repair to replace the blind nuts and I siliconed each fastener when I reassembled the roof rack and brake lights just as an extra measure of precaution. I love my truck but what a nuisance leaks are.

 

[SUBURBAN5]

I had an '88 'Burban that the sheet metal above both rear wheels rotted away. I discovered that when I replaced the rear speakers. That was an easy fix. My '99 'Burban leaks in the right rear and sometimes under my weathertech floor mat on the front passenger floor is covered in condensation and the carpet below is wet. Haven't found that cause yet. For the right rear, so far I've: had the right rear glass removed and reinstalled. My body shop guy laughed at me when I asked him to it, but he was shocked when he removed it and discovered about 22 inches of the top rear window seal was not sealed. That reduced the water infiltration, but didn't stop it. Next, I replaced the cargo door hinges (a really unpleasant ordeal, though the doors are nice & solid again), but it still leaked, just not as bad. Next, I replaced all of the rubber weatherstripping for the cargo doors 100%. It is now much better, but still leaks!?!?!?!?! When I'm parked, the front end is higher than the rear due to the incline in front of my house and other than the car wash, water doesn't get in there at all and even the car wash now may or may not add water. I pulled back the rear carpet up to the right rear wheel tub to see what I could see. At the rear of that tub there is some rust, telling me it's been wet for a while. Last time it rained hard, this area was wet. Metal above the wheels is solid so I am baffled where the water is getting now, though there are seems that could be leaking. Need to pressure-water-test them when it gets warmer and see if I can discover the access point. Very frustrating. Oh, one of the first places I looked for the leak was the roof rack and rear brake light assembly on the roof. No water getting in there, but I did manage to spin three of the blind nuts that the roof rack screws fasten into. Another fun repair to replace the blind nuts and I siliconed each fastener when I reassembled the roof rack and brake lights just as an extra measure of precaution. I love my truck but what a nuisance leaks are.

I had similar issues. Front is 2 places for mine cowl/hvac housing. Rear was seals, lights, and glass seal. Check your rear pillar. You'll see a plastic thing with rubber flaps. 2nd just because you changed your seal it doesn't mean it fixed it. I replaced most of mine and water was coming in every car wash. Luckily my truck was stripped to the bear metal at the time lol. My advise climb on your roof shine the hose down like you putting out a fire or copying rain and you may see water dripping in. I noticed it with the headliner off or pulled down a little. The fix I did was add home cheapo insulation on the top of the barn doors and that fixed mine. You could also try to install foam cord like 1 road did lol. Never tried it but wouldnt be surprised if it worked.

 

[Pinger]

My first thought was that it was coming in through the wheel arch but the location of the damp and it being a pretty fresh truck saved me that anguish. Pretty sure it's the side glass. Weather and other pressing stuff is stopping me knowing for certain.

Broad agreement here though - that a leaking truck (any vehicle for that matter) is a pain in the arse.

 

[mars2878]

I would run tape along the 1/4 window seams. If it stops, then it's the window seal. If it continues. then it is something else.

 

[Pinger]

I more thing to check out theres a seam on the roof edge of the pillar with the ls/lt badge. Over time it will crack. I doubt it's your cause. But seal it if its cracked before it gets worse. You cant miss it. Just go to the top if the pillar and you feel a small seam

A handful of hair-line cracks - is that enough to cause a leak?

 

[SUBURBAN5]

A handful of hair-line cracks - is that enough to cause a leak?

Its enough to rot the metal. Especially in extreme climates

 

[Pinger]

Its enough to rot the metal. Especially in extreme climates

Ehhhh????
Are you saying that the metal underneath the seam sealer has to be rotten to permit a leak? Or can the water just permeate the sealer and find it's way into the cabin?
Please say the latter!

 

[SUBURBAN5]

Ehhhh????
Are you saying that the metal underneath the seam sealer has to be rotten to permit a leak? Or can the water just permeate the sealer and find it's way into the cabin?
Please say the latter!

Lol no I'm saying if it has cracks it opens 2 doors 1 water leak 2 rotten panels. If you address the cracks you take care of the water, doing that you take care of dirt and other crap leading to rust

I'm no body expert but any cracks of seams should be addressed. That's why in the front under the cowl if the seal cracked it leads to water intrusion under the dash. Imo same theory around the rig

By any means I'm not saying your burb is rusted lol. Wasnt trying to paint a bad picture. Just pointing out what could happen

 

[Pinger]

Lol no I'm saying if it has cracks it opens 2 doors 1 water leak 2 rotten panels. If you address the cracks you take care of the water, doing that you take care of dirt and other crap leading to rust

I'm no body expert but any cracks of seams should be addressed. That's why in the front under the cowl if the seal cracked it leads to water intrusion under the dash. Imo same theory around the rig

By any means I'm not saying your burb is rusted lol. Wasnt trying to paint a bad picture. Just pointing out what could happen

I get it - but it did ***** me a bit! Truth is mine (miraculously) is too fresh for it to be rotten.
How though, do I best seal those cracks? Firstly, thinking that whatever I use it is probably better left for now until I can get it thoroughly dried out.
Should I try and get something (what?) to go directly into the cracks to fill them or something to more generally apply over the top of it all?

 

[SUBURBAN5]

I get it - but it did ***** me a bit! Truth is mine (miraculously) is too fresh for it to be rotten.
How though, do I best seal those cracks? Firstly, thinking that whatever I use it is probably better left for now until I can get it thoroughly dried out.
Should I try and get something (what?) to go directly into the cracks to fill them or something to more generally apply over the top of it all?

That's the real question. What to use. I've used 100%silicone from home cheapo. But I've been told that's incorrect to use. Also a hack. At work we use a 2 step fusor for trailers and metal. That stuff is correct I bet and its expensive. But its messy and dries quick. But I believe it's what they used at the assembly line. My 1st approach find the leak and then get back to us. For example say it's the glass. Shes gotta get pulled and redone right. I wouldnt try to band aid that