Rainwater Leak into 1978 Shortbed Cab

[gmbellew]

Originally Posted by gmbellew

I know this is an old thread, but wondering if anybody had an update. I have recently experienced the same thing. I suspect it is the windshield gasket along the top of the cap corner on the driver side, and it is running down the A pillar and into the cab along the top of the dash.

I plan to soak water into the cowl area to rule that seam along the firewall out. if that doesn't produce water, I plan to seal along the top of the windshield and then soak that area after a 48hr cure to see if I have resolved the issue.

to post my resolution, I cleaned the cowl drain outlets at each fender, flushed water, and repeated until nothing else washed down. I couldn't believe the amount of stuff that came out after 30 years. I also sealed the top of the windshield gasket to body gap. everything has been fry through several rainstorms. I suspect the biggest issue was the stuff in the cowl drains, but I can't be certain. hopefully this helps somebody else.

to access the cowl drain outlet locations, a plastic trim piece has to be removed at the base of each fender behind the wheel wells.