I was washing truck and saw some of the cork looking material is missing in drip edge what is it??

 

Cork? Uh-oh......Sounds like a hack's "repair"!


It should be seam sealer like 3M's Drip-Chek which is UV tolerant. Google it.

 

Agree with HIO, just bought a tube that goes in a caulk gun at parts store and redid my drip rail and both bed sides along the bump........

 

Is it kind of yellowish in color? On my truck po used great stuff to try and fix a leak in drip rail.

 

The front and side roof drip rails were not part of the roof panel, they were separate and spot welded in place.

FoMoCo then used a paintable caulking to fill in the gaps and smooth the drip rails. Over time, the caulk chips off, water seeps in, the drip rails begin to rust which soon spreads into the roof.

This problem not only affects 1961/79 F Series trucks, but Passenger Cars as well, especially those with vinyl roofs.