I agree on the bondo/body filler - mix problem or just old stuff. If you can, I would park the truck in the sun for the next week or so (if possible) to let the roof heat up to make sure the body filler is completely dry. That is unless he is going to bead blast all the areas that got body filler to make sure its out. Think about it, if there was a mixing problem or old stuff, where else did he use it on the truck??? Did you find out just what brand of body filler he used. We have had BAD results using hardener from one type/brand of body filler with another. They could either harden too much and shrink or not harden at all. BOTH have the chance of cracking. NOT ALWAYS but who wants to take that chance when the paint has been applied. Acceidents happen and sometimes you forget which hardener goes with what body filler. Most of the time its just laying on the shelf... Things get mis-matched... ;o( I know that doesn't make you feel any better. I really am sorry for what happened. SUCKS.....

 

Truck will be in the sun for the next week or so so hopefully that shows whatever other problems there are if any. He didnt do a repaint of the truck he only shaved the drip rails and welded the seam then "spot painted" the top of the cab. The truck will get repainted eventually but on a college students budget that wont be for years so i figured fixing the rust and spot painting it was the best route to go for now

 

I know its been a while just an update on the drip rails and that crack. The crack didnt grow any more over the next month or so and the passenger side didnt crack either, took it to my body guy and he re did the area for free, so far no issues but it has only been 2 weeks. I'm still thinking it was just a botched body filler mix.

 

When using fiberglass to fix metal the problem is the metal and fiberglass shrink and expand at a differant rate which causes the cracks. I have seen people pop rivit scoops on there hood then use fiberglass to smooth in and it almost always cracks. Good luck

 

Glad its working out, as soon as I scrape together some money, I'm gonna turn loose my body guy and give it a close shave.

 

Good to know i wont be using fiberglass for body work. The drip rails were given a thin layer of bondo to smooth things out after the rust was repaired and i believe that was the culprit.