I just finished the other part of my roof rust problem last week with the A-pillar. But I have seen that it's pretty common with others of around this year in the exact same spot. I've even seen an earlier one with it too.
So, what makes them rust out in these specific spots?

 

Not sure what your referring to. I've never seen roofs rusting. Only cracks at the top rear corner of the door window from body flex.

 

my friends 92 Trans Am hard top has rust all over the pass side roof.

 

the roof is on top? it get bakes by the sun all day long and water sits on it, along with bird crap and everything else out there. Same with the hood and hatch, thats why the paint/clean fails there first. Once the paint is compromised, rust starts

as for the a-pillar, i usually only see that spot rot on t-tops cars, havent seen it in recent memory on a hard top car.

 

I haven't seen any rust either. Mine has the body flex cracks and my other one is fine, only the clear coat is coming off. Pictures?

 

I've seen quite a few T-Top cars with the black center divider rusted; mine is; Mine came with a spare, but it looks like its been repaired badly before, so its not going to be used.

 

oh yea? how come it doesn't happen to the passenger side? and water doesn't even really sit in these spots.
I've only seen it on the driver side, and then all the way down the a-pillar.
I have pictures of mine.

 

it is!

i havent seen it often on the passengerside either. Maybe its more on the driveside in those places because thats where people grab when getting in and out of the car, dirt and oils from your hands, plus just the wear on the paint could defiantly cause rust to start over time.

water sits on the top of the car, it will form beads and sit there. that "can" eventually cause problems, but it takes a long time.

 

good contributions. but I am still thinking there is something else to this.

 

maybe a production issue? not proper rust proofing in that area or something along those lines. Maybe on the underside of the metal before it was welded together? lazy assembly line workers

 

I've heard it rusts from the inside-out. I have seen MANY Camaros like this. Maybe its caused through the driprail somehow?

 

I agree with this. Maybe a pin size hole and maybe temperature changes midday heat -> late night cool down + dew (if it sits outside) = condensation? under the panel... maybe??

 

yea I guess that wouldn't happen if the rust proofing was on their right.

 

I can testify to the "bird crap" theory...my son left my car outside uncovered for 2 weeks while I was out of town. washed all the birdy doo off, and most of the paint underneath it came off as well. The poop cost me a paint job

 

Ive seen more rust around the upper windshield corners. Even my spotless 92 had a bubble on the drivers side I had to grind out

 

I bought my '91 t-top with the roof covered in surface rust. Cheap water-based primer had caused all the factory paint to flake off, and it had never been repainted. Also have a few faint spots around the windshield trim where rust is starting to develop. That shouldn't happen IMO to a car that's spent its whole life in GA and FL.

 

Wow. FL and GA. Now I don't feel so bad because of my spot by the windshield moulding on my IL car. LOL You're right it should not happen.

 

during the 80's especially the last half GM used really really craptastic waterbased paint. the clearcoat wasnt much better. the oem paint wasnt that much better than bare metal. when i had my formula repainted i had it taken to the metal. i was there when the paint ws removed off the hood and roof and the rust was really evident under what looked like solid paint. the paint actually came off in large flakes partway through sanding.

i would say to blame the greenies for forcing shtty paint on the public.

 

yea I've been aware of the crappy paint used in these years. My instructor actually told my class about when that was going on and he had so many cars to repaint.

 

I've got this exact same problem in the exact same area. Mine is rusting from the inside out as well.

 

my rust spot.. i ground it out and filled it. i bet that part of the roof gets nicked more from people putting things on the roof, or grabbing the roof while wearing rings. it only takes one large nick to start the rust process

 

My theory is it is rusting from the inside out(condensation etc,), where the spot welds are .
I have seen three 3rd gen cars rust along these same areas here in Texas . There is no way for it to rust out from the outside as all three cars had good paint and were not holding any water in the rusted out areas .

 

my roof is rusted out around the hinges for the hatch. is that a common location?