I've noticed a lot of threads recently about finding water on the passenger's side floorboards, and it is usually caused by your sunroof drains being blocked. I'm not sure how it ends up on your floorboards, but in most cases, cleaning these drains will help get rid of your problem. Not only will you have to tear up your carpet to get it cleaned and dried, you will have a hell of a time trying to defrost in the winter when you have a very large amount of moisture in the air because of the nice, warm water inside the cab. Here are some signs your drains aren't doing their job, below the pictures are links leading to the full sized ones for details. You may notice discoloration on your fabric, this is a good way to tell if you don't have people sitting in the passenger's seat or don't check to see if the floors wet. It will also feel like you have your own Hawaiian island inside your truck because of the large amount of humidity. http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0530.jpg http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0538.jpg This area is usually where you feel the water's highest point, and underneath the floor mats will be nice and warm and soggy. And eventually will start to smell if left unattended. Did I also mention this will make your defrosters useless? Of course I did. http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0539.jpg Here is one way to clean the drainage system: When water gets through the sunroof's weather stripping, it goes down into these drains, you have one on the front left, and one on the front right. To make sure they are clean of all debris, take a semi-thick gauged, strong, flexible wire, and run it into the drains as far as you can get them. Use something like lead solder or a similar size wire. It needs to be strong enough to push out gunk without crumpling up inside the drains. Here's a picture of the passenger side drain: http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0531.jpg You're going to want to have a wire long enough to reach as far down as it wants to travel, it's about the distance from the roof to the floorboards, about 6 feet should do fine. Once you're done with that, you should find the drain plugs that are underneath the rocker panels below the front doors. They're round and black and about an inch across. They'll look like this: http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0532.jpg Here's where they are located: http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0537.jpg And here's the view from underneath: http://img.photobucket.com/albums/v335/andrewdw/sunroof/Photo0535.jpg Stick your pinky or any other finger that's small enough into the hole and see if you can feel any sort of gunk. With the drain plugs out, take some water in a bottle, cup, etc, and pour it slowly into the sunroof drain. With the drain plugs out, water should flow freely out the newly opened hole. Whatever gunk or grime had been accumulating up there should empty out with the water, leaving your drains clean. There are also drainage slits along the rocker panels which should be cleaned, because you have to put the drain plugs back on, and water has to get out somehow. I wasn't in the mood to crawl under the truck and see where they are located, so if anyone wants to contribute, feel free. To double check that everything is clean, put your finger back in the hole and feel around for mud or any sort of junk that the water didn't flush out. Replace the drain plug so no debris can go into the hole. Pour some more water into the drains and look underneath the truck, and if you're clean enough, the water should be draining fine. If you don't have puddles underneath your truck, your drains are still clogged. You can try to remedy that by removing the drain plug once again, using an air compressor on the drain and trying to force whatever's clogged out. Pour water back into the drains to see if you've cleared it. Remember that mud turns into dirt, which when hard can take a lot of time to make it liquidy enough for it to drain. Also, if your sunroof's weatherstripping/seal is old, dry, or cracked, it may be letting in too much water to handle causing it to not drain fast enough. Replace it or use moisturizers on it. If anyone would like to add/change anything, let me know so I can fix it. If anyone has any other methods that they'd like to write about, feel free.