Hello all! Just joined FTE after recently purchasing a 1979 F250 to restore.

OK, 'restore' is a big word. I want it road-worthy, reliable and "load-worthy", and to last 5 ~10 years. This is going to be a working truck.

Anyway - think I've got brakes, steering, etc. well under way. Drive train is excellent. Body is very good. The frame is another matter. You've got a worn brake shoe? Replace it. But what do you do when you've got a rusted-through frame?

Under the engine and the cab, frame is perfect, having been protected by decades of grease. But the box is rusted through, and the frame beneath it is pretty rough. Main rails are pretty heavily rusted. And most cross-members are rusted right through at at least a few spots. An indication: the upper shock mount, on the frame, was broken right off, I think largely because of rust degradation.

Obviously I'm going to grind it all down to bare metal, but then what? Can you just weld/bolt reinforcing plates onto the old frame? I don't have time to strip it right down to the bare frame and dip it, like a full restoration. At most I might take the box off to work on it more easily.


Any good ideas will be greatly appreciated.

 

If the damage is severe it might be better to splice in the rear section of a good frame. Seems to me, this would be better than trying to repair the damaged frame. Welding on a frame is usually not advised due to the potential for creating points for stress cracks. Frames are designed to flex and stiffening the frame in the wrong places contributes to this problem.

 

Sounds like finding a donor truck at the junk yard would be faster and cheaper.
You could get a solid frame and not have to worry about bracing everything up.

 

I hear ya - and thanks. That does sound like the 'right' way to do it. I'd love to do the frame-swap, I really would, but the truck has to operational in max three weeks with only evenings to work on it, including brakes, brake lines, steering linkage, broken leaves, new shocks.

But what can I reasonably do without going that far? Thanks for the note on welding. Now that you mention it, that sounds familiar. I notice that most frame add-ons, like spring hangers, shock mounts, etc. are bolted on. Was thinking of fabricating a few cross-members plus a few shaped plates to go on the rails, and bolting them in place. Or is there something I've missed that would make this insane?

Like I said, totally open to anything that doesn't involve a frame-swap.

 

Well.. Truck frames crack and weaken all the time, old or new. I know your problem is rust but I'm sure plates would be fine, The reality of the matter is you probably want to do it yourself... don't we all. In this case I would recommend you get it looked at and repaired by a profesional. He'll know exactly how to strengthen rather than weaken the structure. I have an uncle that runs logging company, his trucks go though beatings on a daily basis. He's had frames crack and repaired as good as new on older trucks and some as recent as 2002's.
anyways best of luck to you.
hope you enjoy the truck for years to come.
Mike

 

In the meantime I've been reading about frame strengthening using added members. I think the box is coming off, the rust is getting ground off, flanges and the like are coming off, and some plates and cross members are getting added on.

Thanks all.