From what I can see: Nissan has trouble with door gasket material being too soft and failing due to normal sources of abrasions. This I observed while at a Nissan Dealership and talking with the sales department about a new car in the showroom that had been visibly damaged by customer use. I would look to check for loose and and damaged rear hatch door weather stripping for the cause of water. Also the rear fender seal if you notice it while in motion as the tires spray lots of water from the road. and the gasket around the rear antenna, or taillights.

I would ask about warranty replacement. Also ask about hidden warranty. If you are not still under warranty I would go online and see if it would work with aftermarket weatherstripping. Try asking service people at several dealerships on the phone asking if there is a well known problem that causes your symptoms.

In searches, I would try Nissan Versa, or other Nissan cars, for similar problems. I hope this helps.

I had the same problem when I took delivery on my '06 Pathy. The dealer said that the seal looked like it wasn't as thick as some of the other ones they had on the lot. They said this could have been due to the heat of when it was installed or something like that. Not really sure, but they replaced it free of charge. NO More Leak!
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My rear window was leaking when I got my Pathy. I crawled back there during a hard rain and noticed that the cables for the rear window defroster were getting stuck in the weather stripping. I had not noticed it when I had ever closed the window. Opened and re-closed the window making sure not to get the cable caught and no more leaks. Now I am just careful when I use the window.