Originally Posted by volaredon
Originally Posted by Dave_J
I have seen so many of these 1972 up truck cabs with a 3 inch long 1/8 inch wide crack in the firewall in the wiper linkage cowl area. I think its a weak area from the stamping that has rusted out. My son has this issue.



of what you have seen is this in a spot where I could easily get my MIG stinger in there and fix the issue? Just thinking ahead.
Ive heard of this before, cracks in the firewall area but have yet to see one.... (I haven't had this issue yet, must just have been lucky/ so far)
haven't had a chance to check out this area on my truck yet though either.
My floor pans are like new so here's hoping that this isn't my issue.
good info anyways because I don't plan on this one being my :last" D/W series truck...

what causes these cowl/firewall cracks? I wouldn't think it would be cab/body flex, as they are full frame. If they were a unibody vehicle that cause would be more understandable.

In the case of THIS truck, I wouldn't think that its /6 would have enough power to "hurt itself"-- relating to body and frame flex....


I had a picture of this crack on my sons truck but can not find in on my hard drive.

The cab does get stressed a lot over the years. Mine when going over a un-even driveway the cab will make a 'BONG' noise when it flexes enough on the frame.

As far as getting a MIG stinger tip in there, I think you could from inside the cab. But I would have someone in the Cowl area holding a 'Copper' backer plate over the crack so you dont just blow through. I have a huge sheet of dead soft pure copper. I just cut a piece and hammer it into the shape I need and hold it under the hole or crack. Check out Mike Finnegan's "Eastwood' Hotrod TV vid on YouTube:

youtube.com/watch?v=huPdLOIA438


Retired, US ARMY 1973-1994
ASE mechanic, Electrical 1994-1997
Retired GTE/VERIZON/FRONTIER 1997-2015


Posting cheap tech help (CRAP) here since Nov 97, 1000's of posts, some may be good.

03 Suzuki Burgman 650(Burger King) Scooter
65 Formula S Cuda
78 Little Red Express Truck
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