Help. Underlay Is Soaked Again, Floor Is Starting To Rust Grrr..
 

I dried out the floor then put the underlay and matting back in and the underlay is soaked again after a week of rain wtf whwere is this leak comming from no evidence in the cab, Has anybody have this problem I have a 1990 reg cab base model no bling... and what can I do to remedy this??? :madd:

Water leaks suck.

Look for any rust around the windshield and rear window. If there is water is most likely getting in there.

Take some talcum powder or silicone grease and apply it to the door seals. Shut the door and then open it. Look for areas on the door where the grease/ powder didn't stick or for areas on the seal where they are gone.

Have a business card? Slip it in the door gaps with the doors closed. Run it down the gaps and feel if the card gets really easy to slide in spots. If it does that could be the source of your leak.

Check your floor pan really good. I've seen body plug leaks, cracks, rust cause the floor to get wet.

If all else fails, remove all trim and head to the car wash. Take someone with ya to help look for the water coming in.

Do you have A/C? Set it on "Recirc" and turn the fan on high. Watch for bubbles out side of the cab whn the wash is soaping ya down. bubbles mean air is getting out. If air gets out, water could get in.

I had a shower head rigged up on some piping. It was higher than a cab. I'd let a car sit under there for a half hour and then go hunting.

I almost bet it's your cargo light if ya have one.

Sounds good to me!:U:

I have the same problem. I think mine is leaking at one of the cab lights. It runs down the pillar and down the kick panel and under the rubber floor onto the underlay. I put a new rubber floor kit in a few years ago when I replaed the skanky old carpet. But before I put it in, I cleaned the metal floor and rockguarded it, so that there would not be any issues with rust from within the cab.

The cowls crack and are common on all 1stgens for leaking and alot of them leak at the flore vent on the drivers side too, here is a link for seeing cowl cracks: FAQ If you open the doors you can see the cowl cracks right below the winshield.

Thanks for the link, this should help.

Thanks everyone I'm hunting
 

I appreciate all your info and have some work to do now I know where to start. Your helpfullness makes this place necesary equipment :yeah: