I've seen quite a few posts about water leaks due to bad water deflectors inside the doors on the 2000+ models. Ours is leaking nicely from both front doors- pour water on the glass and watch it come out out from under door trim near the speakers. So naturally I go to gmpartsdirect to check pricing and they tell me both part numbers (25742368/9) are not good. The dealer wants at least $55 each.
So, the question is- is it possible to fix the dreaded water deflector problem without actually replacing the deflector (If it'* not ripped, but just has sealing problems). I am thinking some silicon sealant maybe? Any ideas/suggestions?

between the deflector and the door itself is a thick rubber like goop that is extremely sticky. Usually if you just press your hand around the perimeter of the deflector that is good enough. the black "goop" is real sticky like I said and it should stick if you do that...

The black goop is a butyl sealant. You may or may not be able to re-seal by pressing on the existing seal. I've tried that, and it resolved leak problem only temporarily. I went to NAPA and found a tube (caulking gun size) of butyl sealant. I had to clean old seal off door frame then re-apply sealant, this seemed to do the trick for me. Part of the problem with these water deflectors is they have ripples in them and are not perfectly flat around the perimeters. Both my front doors leaked just the same way as you descrbed.

Thanks for the info! I just finished both doors. Passenger side had the deflector barely attached at all, driver side was flopping around the front corner. Here is what I did- peeled the thing completely, cleaned the door with a solvent, then reattached and went around with a lot of pressure to make sure it sits. I had one corner on both doors where it just would not stick. I ended up removing that part of the sealant, cleaning both surfaces, then after warming the goop in the sun, shaping it back into a long narrow tube and pressing back on. So far it seems to hold tight, and does not leak. I am a bit concerned about how this stuff will work in winter- if it gets softer when warm, it probably gets hard when cold, and falls off?

By the way, I got a reply from GMpartsdirect about the correct part numbers for the deflectors. If anybody needs them:
25742368, has been replaced by 15212771
25742369, has been replaced by 15212772.
They are very reasonably priced there- only $19.83 each