With all this rain we've been getting in the Northeast lately I'm at my wits end with tracking down a leak. I knew that my rear window seal was bad when I got the car, so I ordered a new one. When I discovered a big spot of hidden rot in the trunk I said "screw it" and decided just to goop the window instead of risking breakage trying to replace the seal using the clothesline method. I sealed all around the seams with 3M windshield sealant, patching up any remaining possible holes with weatherstrip/rubber adhesive (which btw is awesome stuff!). It fixed all of the leaks around the window, or so I thought.

I sprayed the area excessively with a hose and found one more leak, which I patched up. For good measure, I sprayed the whole area with rubberized undercoating, hopefully getting any miniscule holes I might have missed. So yesterday I was happily cruising along in a lovely drizzle/sprinkle and I noticed that there was water leaking into the bottom of the back seat. With the seats out I found that it was entering somewhere behind the drivers side rear wheel-well support (where the seatbelt is) and trickling down to the floor. So once again I take out the hose and spray down the area....nothing. Yet it is raining again later and I see it begin to trickle down!!! It is coming above the door, so I don't think it would be the seal. I'm beginning to suspect the sunroof drain?? Does anyone know where/if the sunroof drains? Could it be anything else? I'm pretty confident the rear window is completely sealed, and I didn't see any moisture around the corner or top. And for some reason I remember reading that the sunroof drained to the transmission tunnel

Edit: Car is 1982 300SD. Also, the headliner looks fine and no signs of water damage or sagging.

__________________
TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth