Wet floors again.

Before everyone flames me for posting this and saying use the search tool, let me say I already have.

So after my significant other drove through a puddle at night on the highway water managed to enter the cab through a body plug above the driveshaft. Turns out the force of the water was enough to blow out the plug and fill the cab.
Secondly the passenger side was much worse (standing water) I'm beginning to believe this is the flawed design by Toyota when it came to air duct positioning. Still haven't pulled the cab air filter to confirm it is soaked but I'd bet it is.

What I'm looking for is where else has anyone traced the leaks back to. I'm not ripping the truck apart again so I'd rather do everything while the cab is gutted.

If you guys can help please just list places you have found to cause leaks.

Thanks.

 

So I have found several leaks and one common one for the most part. We all know the cowl leaks but on mine the sealant on the vertical sheet metal that is spot welded in place and the caulked is no longer sealing. I watched the water in the cowl weep through this sealed area and just dribble around the air box which then follows the firewall all the way down to the floor. I'll tamper with trying to put up some pictures this evening after work.
Common issue with a twist I guess.
Maybe some urethane flashing sealant will do the trick.

 

Pictures would be great! I'm surprised about the body plug. I will have to check mine out.

 

Apparently I must not know how to post photos lol.

I have one of the cowl upgrade. Part of the Toyota TSB.

 

I have added some sealant surrounding the intake duct of the AC system in the cowl. Turns out the original sealant had rotted away. Won't know if this is the only leak until our next major rain.

The body plug is directly above the driveshaft just before the parking brake cable exits the cab. Just added a bit of RTV here and pressed it into place. It's not the first plug to leak in my truck either.

The HVAC box also had a lot of water in it drain was not plugged or blocked just the parking provided just enough incline to keep it in the box.

 

Been really wet down here. My guess is it was a little more than a puddle. Good job figuring it out and taking care of it.

 

Once you have the interior gutted, go out after dark (darker the better) with two people and a bright light. One of you work the light from the inside, and one look from the outside. Where you see light it will leak.

Then swap, putting the light outside and one watching from inside. Same deal, but you may find different places.

Like roof leaks that travel from the leak point to a different drip point, this *may* not find everything. But I bet it finds enough to be a helpful start.

 

All true. I've done this the past two nights during our heavy rains. The HVAC box had water in it but it was from the cowl intake not sealing off. Some would enter the HVAC box the rest would go around following the HVAC box and firewall. I'll know more once we get some additional rains and the sealant cures fully. 7 day cure time 10 min skin time. It's a urethane mix sealant from the hardware store I've been told works well.