97 3500 Extended Cab Water Leak Near Back Window

[wirlybird]

Hi all,
I have found a water leak inside the cab near the top corner of the rear window behind driver. It drips a little from the roof area closer to the window.
It's an extended cab. I see there is a molding on the top edge of the roof that comes down and meets that same corner of the window on the outside. Is this a leak prone area?
Looking for advice on what to do before just loading up with silicon.
Is it a window gasket or something else?
Thanks for any info.

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[EJ_74]

Any chance the third brake light is leaking and running down to the corner?

 

[someotherguy]

Any chance the third brake light is leaking and running down to the corner?

Third brake lights often a sore spot by this age, because the gasket has hardened, shrunk, cracked - as well as the lens itself.

Either that or the glass itself is leaking. They're glued to the body with special window urethane adhesive, and over the years it can fail - but can fail especially if the glass was replaced and they didn't do a good job.

Richard

 

[wirlybird]

Didn't think of the third brake light. I will check that first.