Greetings,
My headliner has been out of my car for a year now so I felt it was time to tackle the leaking sunroof. I unplugged the tubes a while back but wisely waited on reinstalling the headliner (1 front is plugged again, and the other front has separated somewhere behind the dash).

Currently I am removing the entire interior including dash to find the break in the tube. I don't intend to simply reconnect it because it will probably separate again. What I want to do is buy some clear tubing (heading to Lowes in the morning) and run a continuous tube from the sunroof to the wheel well.

1.) Has anyone done this?

Has anyone else removed their entire dash before? I have the front dash almost out, and the carrier (metal structure) is behind it. Is all this necessary to get behind the rubber matting? ( I want to avoid cutting it) I'm not sure where exactly the joint is.

2.) 3 of my tubes are black, the Dside front is clear(ish). Does anyone else have mismatched tubes?

3.) Under my front upholstery in the foot wells there are pads bonded to the floor pan. They are some sort of hard mat - what is this?

4.) I don't smoke, but the previous owner did. Don't smoke in your car! The smoke breaks down the headliner glue and causes it to fall down sooner. (leaking sunroof contributes as well).

Any other suggestions? I want my new tubes to handle as high a flowrate as possible. I plan to stick the largest diameter tube I can fit into the A pillar.

-Shawn

Going with tubing larger than diameter of the hole wont gain anything. Match the tubing to the existing diameter. I'm not a dash person though to help you with the rest of it.

i have heard of people using aquarium tubing to replace the drain tubes, but with no real experience on the Bonneville'* drainage system, i dont know if that would work or not...

Update -

I have reconnected my Pside front tube. There is an access hole in the rubber matting which allows you to fish the two ends out and reconnect them. It isn't easy but it saves removing everything in the dash to get to it. Removing the dash is not desirable because the steering column must be lowered and probably even removed. For the Dside front tube, there is no access hole. Should yours become disconnected, I recommend locating the access hole for the Pside, and then cutting a small square flap into the rubber matting on the Dside at the same position. Shame on GM for making the tubes in two pieces.

The ends of the tubes terminate in the front wheel wells in a nipple. This nipple is a nice design in that it prevents gunk from getting splashed up in the tube, but the nipple is just too tight. I recommend that as part of yearly maintenance, you treat the nipple with silicon to keep it flexible. When it dries out it gets stiff and seals itself shut. In fact, if your tubes become clogged, I recommend first pulling the fender liners, and giving the nipple a squeeze - water will probably come out. Should you need to clear the line further, try threading some flexible wire up from the bottom or down from the top, before pulling the headliner.

As for the rear tubes I recommend pushing the tube through the body grommet to clear the nipple so the water can drain straight out. Tropical storm Fay come through here and so far my sunroof hasn't backed up with water - tubes are flowing sufficiently. I apologize for not having pictures - I had to get the car back together in a hurry.