Replacing a single frame rail, can it be done?

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nitrocharger

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Hello, new to the group but have had the same Squarebody for 30 years. I bought this truck in HS with my Dad and its been off the road for the past 25 years. I started a frame-off a year ago as one section of the frame had irreparable rust damage. I bought a new-to-me frame but I wanted to explore the possibility of swapping the good frame rail in the original frame with the donor frame rail. The benefit would be that it keeps the original VIN stamping and I get to keep a piece of my Dad and I. I understand its a lot of work drilling out rivets and replacing w Grade 8 hardware but is there any alignment that would be lost? Will the original holes line up? One truck was built in Baltimore ('76) the other in Flint ('75). Currently both frames are rolling chassis. I'd be interested in hearing from someone that has actually done or attempted to do this to get their perspective.
 

Strick

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I've knocked the rivets out to remove the crossmember on dad's C20 Crew & have also moved the spring shackle that was riveted.
You  should be able to replace the one rail by doing just as you stated. It'll be more work but retaining the VIN plus the memory of "daddy's hands" will be worth it IMO.
Welcome to the site from steamy Central NC. Provide us with some pics of your project.

HS
 

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I would probably call a frame repair shop, and see what they have to say. What they would charge, why it would or wouldn't work, etc. If there are no frame repair shops in your area, then just call one in a different time zone. Call one that's in Hawaii. Doesn't matter where they are in the USA. After all, they specialize in frame repair. If anyone has the answers, its them. Just for good measure, I would call more than one shop.
 

bucket

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I would probably call a frame repair shop, and see what they have to say. What they would charge, why it would or wouldn't work, etc. If there are no frame repair shops in your area, then just call one in a different time zone. Call one that's in Hawaii. Doesn't matter where they are in the USA. After all, they specialize in frame repair. If anyone has the answers, its them. Just for good measure, I would call more than one shop.

If you call any frame shop, they will either say to replace the whole frame, or say "get lost bud, we don't want to deal with your rusty truck."

Besides, there's people here that have done frame work and worked in frame shops. There's no need to call random businesses and bother them.
 

bucket

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Yes, you can replace just the one rail. Time and money wise, it makes no sense, but for sentimental reasons, it kinda sorta makes sense.

If you are replacing ALL the rivets with bolts, make sure the frame stays square as you bolt it all together. I'd start at the front. Drill out all the holes from ~3/8" up to 7/16" and assemble with grade 8 hardware. Preferably bolts with flange heads and also pinch-loc flange nuts.
 

Old Guy Bill

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I’d suggest fabbing up a jig to hold the frame if you want it to be as best as possible.
 

Ricko1966

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Spray paint all the frame junctions before disassbling the old frame. You can use the paint lines as a visual aide as to something out of square. Also if you don't know 3 4 5. Rule for checking square learn it. I'll describe it,but Google or wiki it hopefully you can get a visual. At a 90 degree junction if measure 3 inches on one leg of the junction and 4 inches on another,diagonally from the 3 inch mark to the 4 inch mark will be 5 inches. It does not have to be inches it can be feet,millimeters,etc. but 3 and 4 =5 .
 

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I get what you're trying to do, but in all honesty, just rolling the complete new frame under it makes the most sense. Unless you're literally replacing the whole body/engine/etc and the frame will be the only tangible thing of your dad you have left. But if you're keeping at least most of the cab/sheetmetal, save yourself the frustration and just swap the whole frame
 

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Not really a big deal to do. While we didn't separate all the way down, we did remove all but 2-3 cross members for repairs/ replacement.

These frames are pretty flexy and aren't perfectly square from new if you ask me. Don't tighten all the way until all bolts are in and really should square up fine as assembled.

Drill out every rivet. Separate into pieces. Drill to 3/8 or 7/16 as mentioned above. Use G8 hardware with the pinch nuts. I also used the AN style G8 flat washers under the head and Nut. I like the AN as they are smaller outer diameter and less play on bolt shank. And ultimately look better. I have a nut and bolt shop near me that probably has 5-10 different styles of G8 washer for any given size. $8 a pound.

We also cut frame in half to shorten and C-notch at same time. My son was 14 at the time and it was his 1st time drilling rivets and using a sawzall and it came out fine
 

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waterpirate

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Check out bendin with Brenden on you tube. It is your time and your truck. Go slow, making a jig is a good start. People here can chime in and help.
Eric
 

bucket

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Not really a big deal to do. While we didn't separate all the way down, we did remove all but 2-3 cross members for repairs/ replacement.

These frames are pretty flexy and aren't perfectly square from new if you ask me. Don't tighten all the way until all bolts are in and really should square up fine as assembled.

Drill out every rivet. Separate into pieces. Drill to 3/8 or 7/16 as mentioned above. Use G8 hardware with the pinch nuts. I also used the AN style G8 flat washers under the head and Nut. I like the AN as they are smaller outer diameter and less play on bolt shank. And ultimately look better. I have a nut and bolt shop near me that probably has 5-10 different styles of G8 washer for any given size. $8 a pound.

We also cut frame in half to shorten and C-notch at same time. My son was 14 at the time and it was his 1st time drilling rivets and using a sawzall and it came out fine

The reason I mentioned drilling to 7/16" is for frame rigidity. Putting the frame together square, it's possible that the original rivet holes may not line up perfectly. So drilling to 7/16 will make them line up. In short, drill only as a connection is being made, rather than drilling all holes ahead of time.
 

Ricko1966

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Check out bendin with Brenden on you tube. It is your time and your truck. Go slow, making a jig is a good start. People here can chime in and help.
Eric
If you don't know how to make a jig ask us. If you make a jug,square the old frame first. No reason to make a jig to hold a frame parallelogram. I think I'd just square it as I went 3 4 5.
 

77Dmax

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I've seen this done dozens of times in the HD world. Lots are replaced due to collisions and other failures.
 

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The reason I mentioned drilling to 7/16" is for frame rigidity. Putting the frame together square, it's possible that the original rivet holes may not line up perfectly. So drilling to 7/16 will make them line up. In short, drill only as a connection is being made, rather than drilling all holes ahead of time.
Pretty sure we drilled out to 7/16, I don't remember though.
 

Strick

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I went 7/16 when moving the shackle from 52" to 56" springs.

HS
 

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