Been trying to find the source of water leaks in our '06 Mustang trunk. I can usually find a couple teaspoons of water in the rear RH wheelwell after a typical Seattle rain. Flipped the rear seats down while parked in the driveway in a heavy Seattle rain and (while using a flashlight) found water seeping in at two locations. Both leaks appear to be between sheets of overlapping spot welded sheetmetal. One was below the RH taillight, the other was up higher, a couple inches to right of the trunk seal, but where two pieces of metal come together and form a small diving board.
Any suggestions how to seal these? Can I seal them from the inside of the trunk, or do they need to be sealed from the outside? (would probably have to remove the bumper cover and trunk hinge to put the sealant where it might stop the leaks) What type of sealer should be used?
Go down to NAPA or another auto parts store that sells body shop supplies and get a caulk tube of seam sealer. About $15-20 but that’s what its for. Just make sure you get it at the seam where the water is coming in and that you don’t trap the water in there.
Ditto for the above advice. I don’t do body work but I keep a tube of Seam Sealer around for the occasional customer with a problem like yours. And it rains as much in Tacoma as in Seattle. Today, probably more.
There is a seal on your tail light and i would replace it before sealing the seam. Water migrates and the seam will wick it to the lowest point. Also, do you have a sunroof. They leak and have drain lines that run down the pillars from the roof. If the hose becomes disconnected or cracked they will drain into the trunk area. Also, make sure the trunk seal is free of debris and in good shape.