Drip Rail Rust

[Bob B.]

Here on the west coast, about the only rust I see is in the rockers, kick panels, and doors, usually caused by plugged drain holes. I have seen trucks from other parts of the country with bad rust in the drip rails and both the inner and outer roof. I have a friend that currently has a '70 short step with rust in those places. We have a good roof and are probably going to just change the whole thing. My question is how does rust in the drip rails and roof usually start? I was thinking it is caused by water between the inner and outer roof, maybe due to a roof antenna or cab lights not properly sealed. I have seen trucks with the drip rail cauking in really bad shape but no rust under it.

[BurnoutNova]

i had one with rust in the roof real bad and it had cablights on it, so i think that had somthing to do with it.

it seems like with these trucks any part of it can rust. it never sieses to amaze me where people find rust. the other day i was at a friends shop and he had a 70 buick skylark he was parting out. it had the best quarter panels and floor ive ever seen on a car like that, but the metal under the vynil top was so weak and thin from rust you could push on it with your finger and sink the roof in on that car. it was crazy.

[special-K]

I think it starts under the seam sealer.I`ve seen that rust on alot of coastal California trucks.I believe fro salt air settling up in there.I have a truck from central CA and the seam sealer was cracked and lifted real bad.Maybe it`s vehicles that spend alot of years in the dry central valley,where the sealer gets dryed out and lifts,then moved to by the coast where salt air is a culprit.
I had a truck from San Diego that had rust there and the top roll of the front bed panel was all full of holes,as well as bottom of tailgate.I stripped it to bare metal and the floor,cab,mounts,and corners were solid as the day they left the factory.
Alot depends on what the water does once through the drip rail.Sometimes it just drains straight down the A-pillar and the base of the kick panel will get rusted as well as the floor.I`ve seem A-pillars rusted.too.I guess if it doesn`t run down the pliiar it sets in the header panel area and rusts that.It may be blockage or the way the truck sits when parked.

[Bob B.]

In addition to water running all the way down the A pillar from the roof, I think a lot of A-pillar rust comes from the door hinges. If the hinges are not sealed good to the pillar, water gets in them. There is no drain at the bottom of the pillar either. The pillar ends in the rocker, and I have seen at least a bit of rust there on every '67-'72 I have looked at. With the fender off, remove the plastic plug at the front of the rocker, and look up from there. I like to drill a hole in the bottom of the pillar, so any water that does find it's way in there can leak into the rocker (and make sure the rocker drain holes are open!).