Originally Posted by
DarkangelGSR
It could be that, but on my GSR that was not the case. Before you go out and buy one, look to see any places on it that have cuts or anypart coming up. If not then it's not the bad guy. My bad part was the gasket that protected my taillights from hitting the trunk, that gasket. Open ur trunk and look @ the back of ur taillights. That black foam looking puzzle piece that goes around where ur taillights goes. That was my leak.
We had the exact same problem (leakage in the hatch, with water accumulating in the spare tire area) and cause (taillights). In our case, the taillight assembly was leaking and you could see moisture inside the taillight lens. Once we fixed it - this was at a body shop, so I'm not sure if they only replaced the gasket or the entire taillight assembly - the leakage problem was gone.