You can weld the frames.
Read down to where it says FRAMES. It's a PDF file.
Here is the whole book. Worth reading. There is another publication that gives pictures that I have saved on a harddrive somewhere but you should be able to find it on-line as I did.
Great info there Will.
This would be the part I was talking about, #4 " 4. Do not weld on frame flanges, including the bend radii." This is what makes it impossible to section or repair a ford c-channel frame. Not to mention the info you submitted is from the fleet class of trucks, not passenger vehicles.
Here is a small list of the frames ford will allow sections on. Notice they are all hydroformed boxed frames. Not C-channel frames.
http://www.i-car.com/html_pages/technical_information/advantage/advantage_online_archives/2004/102504a.shtml
A little more valuable info, which states the same thing as your info Will, you cannot weld on the upper or lower flanges, including the radii.
Crack repair is generally a business decision as most vehicle makers provide limited information regarding this type of repair. Ford, however, provides the following information regarding repair of frame rail cracks:
Ford's Recommendations:
Ford recommends that cracks resulting from repairs can be welded and then should be reinforced by installing a piece of the same material and thickness that extends 100–150 mm (4–6") beyond either side of the crack and is welded completely around its perimeter. There are four restrictions regarding the repair of Ford frame cracks:
Cracks cannot be repaired within the crush initiator area.
Cracks caused by repairing a kink cannot be repaired.
Cracks located in the area of the steering gear cannot be repaired.
Cracks located on the flange area of a C-channel frame should not be repaired.
Generally, frame cracks that should not be repaired include those:
near the steering box area.
near a suspension mounting area.
on the top or bottom flange on a frame with an open C-channel design.
caused by straightening an area that was previously kinked.
Basically, my comment of "you cannot weld on ford frames" was a general comment, which does apply to the OP's question, but isn't neccesarily the bottom line.
Like I said before, anything you do to your frame makes you liable for the outcome, good or bad, unless you follow fords reccomendations to a T. And there are no procedures outlined by ford for the repair you want to do, therefore it is not a viable repair, and should not be performed, unless you know the liability you are taking upon yourself, and the next stop for your truck is a crusher. If you sell this truck after making the repair and it fails, injuring someone, you are automatically at fault. Just something to think about.
While it may be more work, the only right thing to do is to change out the frame with one that is in better condition.
With that said.
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