I have a 48 GMC and there is lead from when they manufactured it on the cowl section where it meets the rest of the body. My question is do I or don't I remove this and replace with the newer polyester fillers available today? Also if I leave it, will I run the chance of the lead cracking and splitting my paintjob down the road? Anybody with a working knowledge of the factory lead please chime in. thanks

Is it still solid after 60 years? Why would it crack now? The newer fillers are really good stuff and do have advantages in application and such but are they actually better than lead? I seriously doubt it!

Sorry I am just paranoid because there was a place that was fixed on the upper back part of the cab that had cracked and split...What causes the lead to split apart anyway?

extreme temps (cold) can cause it to split but most of the time it is so flexible that it simply warps in and out of shape.

the old Lacquer paint seems prone to crack anyhow....the newer poly paints take a bit more abuse from temps.

Thats my understanding anyhow

I'am doing a 51' and had alot of work on the cowl and windshield channels and although the modern fillers are great this is a high stress area in these cabs especially were the roof pillar and lower windshield channel meets the cowl at the belt. Yes its more work! but worth it IMO. Just make sure you don't lead in the little square drain holes in the windshield channel corners " they serve a purpose''! Like old red said if the lead is good after 60 years nothing short of a torch will take it out, just add to it.