Running out of options

My wife and I have a 2004 Chevy Colorado that has been leaking rain water into the cab for about a year. The first trip to the glass guy saw the rear window being resealed. The front windshield got a crack so it was replaced and resealed. The water was still leaking into the cab. Last week we had the brake light above the rear window resealed. Last night we had some bad storms and the cab was again full of water (ok…not like a fraternity prank full of water…but it was sloshing slightly on the floor of the vehicle…maybe a half inch) We are at wits end about what to try next. With a window “expert” having failed, we don’t even know who to take it to. We know we will have to replace the interior carpet and insulation when we do get this problem solved, but we cannot even begin that process. With the weather getting warmer, the smell is not the most pleasant thing you would want to experience. Any help would be appreciated.

I have no idea, but you might want to cut out the wet carpet now and replace it with cheap rubber mats. there’s a lot of electronics in that cab that moisture will attack. Have you tried hosing the outside to see where water first appears?

Start by having someone sit in the car while you drench the cab with a hose. See if they can see where it’s leaking from. Then we can work on how to make it stop.

It sounds like the focus has been on window seals. Has anyone checked door seals, or the cowl area under the hood?

Other leak possibilities include clogged door drains which result in water coming into the cab, and a leak in the front cowl area allowing water to leak in behind the dash, sometimes caused by either rust or clogged cowl drains.

You should pull up the cowling and inspect the intake for the HVAC system. The cowling is the piece that covers the area from the base of the windshield to the hood. Underneath the cowling is a something that looks like stove pipe, but only about a half inch to an inch tall and 4 - 8" in diameter. This is the intake for outside air to get into the HVAC system.

Chances are that this will be OK unless you see a lot of rust and holes at the base. Now look to each end of the cowling area for the drains that go down behind the wheel well and forward of the door on each side. If these get plugged up, then the water accumulating in the cowling area could rise over the top of the HVAC intake and that is where your water is getting in.

We know we will have to replace the interior carpet and insulation when we do get this problem solved, but we cannot even begin that process

Yes you can and it will be a lot cheaper and faster in the long run if you do. I’ve been down this road before and here’s what I would do:

The carpet and padding MUST come out no matter what if you plan to salvage the vehicle. If you do it now, you can likely save both the carpet and padding. In addition, once mold starts, it will affect everything in the interior, not just the carpet so it’s important to act quickly to mitigate the expense.

It is not that hard to remove the carpet and padding. The seat(s) have to temporarily be removed if you prefer not to cut the carpet but it’s not really that difficult to remove them. Once you get the carpet and pad out, lay the carpet in the sun to dry for as long as it takes. The pad can be wrung out and once you do, you’ll realize the wisdom of getting it out of the truck. There will be many gallons of water soaked in there and it would never dry out while in the truck.

Dry out the inside metal surfaces with towels, etc. Lay paper towels along the firewall, thresholds etc. Basically the sides of the passenger tub. Close the doors and use a garden hose to flood the exterior surfaces. Open the doors periodically to inspect the towels. A wet one will be obvious. Look up from there. Fix the leak and re-install your pad and carpet.

I’ll just add that a flashlight is helpful as it will reflect off any water getting into the cab.

Ed B.

There’s three Technical Service Bulletins for your vehicle that addresses water leaking into the interior.

PIT4317-Water can leak into the interior thru the HVAC case.

PIT3523-Water can leak into the interior thru the roof seams.

04-08-57-004B-Water can leak into the interior thru the cowl at the base of the windshield.

Tester

Yikes! Get out the oars!

I know this sounds silly but I did it with my old Prism for at least temporary relief. When I had a leak problems the trunk, I drilled drain holes in the low points, coated with the hole side with grease then plugged the hole with a rubber trim plug. When ever it rained, I would just snap the plug out while it rain. Yah, you should remember to keep it plugged when driving but I had an old car and draining it quickly seemed the cheapest answer short term. Yes, you can do it to the floor pan, just be real careful where you drill. Don’t let water collect anywhere on the interior of your car, especially under the floor mats. For actually fixing it, lots of good suggestions all ready. Being a “many boat owner”, I have a fetish for putting drains in everything exposed to rain.

Also, once you have had significant puddling on the cab interior, it will begin to rust especially while the carpeting is damp. Once you find and fix the leak, peal everything back and with a foam brush, paint the floor board with red grease in a thin layer which doesn’t smell at all. Place wax paper over the very thin layer of grease which will arrest any rusting . Then just replace the carpet and pad. Most floor boards rust from the inside out . Check after a year or two and redu it again if you want.

ac condensation drain tube may be plugged with leaves and/or other debris, so the condensation is draining into the cab . . . quite common on all sorts of vehicles