what is the best way to fix a cracked frame ? went to remove steering box to change seal and found crack between box bolts right behind shock tower been running it no problem though If i take off box will the frame twist its a76 f-250 2 wheel drive thanks

 

Same thing same place, I drilled a hole at the end of the crack took the grinder cut a v groove along the crack and welded it up. Put the steering box back on. I look at it all the time seems to be holding. Not sure if that's the correct fix, but that's what I did.

 

It was Properly done, the welded area will be as strong as the rest of the frame.

 

Most correct way I've ever been told.

 

Common problem. The original bolts were too short, did not use self locking nuts. Nuts worked loose, gearbox began to wobble, frame cracked.

1978: Ford finally offered longer grade 8 bolts (384737-S2 - 7/16" -14 x 3 5/16") and self locking nuts (382599-S100), but this was faaar too late, as the problem began in 1969.

Dealer fixum: Weld frame crack, weld extra pieces of sheet metal over it, install longer grade 8 bolts and self locking nuts.

 

Thanks for that did not know

 

I have a related question.

Do you know about welding onto a ford truck frame? I'm putting a 73 2dw bed onto my 76 4wd truck. Bed holes are wider than 76 frame. I want to weld brackets onto the frame to receive the bolts through the original holes in the bed.

I'm hearing both ways - "sure, weld away" and also "Don't weld the frame, it will make it brittle next to the weld and the frame will crack" The alternative seems to be to drill 1/2 in or 5/8 inch holes in the frame to bolt on brackets. I'm told the bed itself has reinforcing at the bolt holes (underneath the bed inside the boxed channel support that sits on the frame), so just drilling new holes ends up with cracked metal in the bed around the new holes.

I found a FOrd service bulletin https://www.fleet.ford.com/truckbbas/non-html/Q18.pdf talking about welding frames to modify wheelbase for different beds and emailed the author, a nice man at Ford. But he just says Don't weld on the frame. I suspect he has to say that because that's what Ford lawyers tell him to say to backyard guys like me. I'm confused by his response because, if you shouldn't weld on the frame, then why does Ford put out a service bulletin telling dealers how to weld on the frame to change wheelbase?

If anyone knows about this, I'd sure appreciate more knowledge. Thanks!

 

Properly done, welding to the frame will cause no problem.
Here's a link to grinnergetter's build thread. This post is a picture of the tab he welded to the frame. He did the same thing you're doing.
His whole build thread is definitely worth the read. Unfortunately a lot of the early pictures have disappeared.
https://www.ford-trucks.com/forums/9...ml#post9247738

 

There are proper welds and improper welds that can be done on a frame.

Can you make a small repair? Yes.

Can you weld here and there? Yes.

Can you weld horizontally in a short area to box in a c channel? Yes.

Can you make a vertical weld all the way from the bottom of the rail to the top? Not recommended. You will need to cover the area in a plate and weld it on horizontally, not all of the way around.

Welding does two things. It hardens the metal where you weld making a stressed area. It also shrinks and deforms where you weld.

Bottom line: don't get too crazy.


There is online somewhere, a 30 or 40 year old military manual for tank and truck welding repair. It is hundreds of pages covering it all. It explains frame repair in detail.

 

Thank you both very much. I spoke with a guy at Lincoln Welders (manufacturer of welders) and he told me that I should not weld on the top or bottom, but it would be fine to weld the vertical part as long as you do not weld within 1 Inch of where the radius of the curve starts - the curve where the frame bends from vertical to horizontal at top and bottom. He said put a straight edge on the vertical section. Then measure an inch in from where the metal starts to curve (where it leaves the straight edge) and that's the start of the safe zone. From what he said, it sounds like welding along the edge of the top or bottom would be okay because it's more than an inch from the start of the frame curve.

And I'm not that experienced, so I thnik it makes sense to have an experienced welder do the work.

 

So after I posted, I got to Grinnergetter's pictures and from what the Lincoln Welders guy said, Grinnergetter's tabs are welded in the "no weld" zone at the curve. He's probably happy motoring and will never have a problem .....

The Lincoln ELectrics site is Frequently Asked Questions | Lincoln Electric I did a chat and the chat guy referred me to an expert in their company who gave me the details about not welding within 1 inch of where the radius of the curve starts.

 

I've dealt with this twice, however I modify the bed to fit the holes in the frame rather than the other way around.

 

Yep and the part that'll be helpful will be about 2 page worth and buried somewhere in the middle of the manual... LoL
( No sarcasm just experience... SFC USAR)

 

Hummm... I've seen that done. Have you hauled loads with those beds? Is the sheet metal of the bed around the new bolt holes you drilled intact? I've been told that over time and loads, the metal of the bed will start to crack at the new holes.

 

LOL about searching thru 100s of pages for the gem you're looking for! I found a hundred page listing of tech specs for differentials that was like that. It did tell me what I had though.