1982 LWB to SWB Conversion

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Travis82SB

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Hey Everyone,

I'm new to the Forum as I am just starting a restored project on my 82' C10 and I'm looking to shorten the frame to take it from a LWB to a SWB. I have spent some time looking around for a decent SWB frame but have not had much luck in my particular area, and my LWB frame is in exceptional shape so Im entertaining the idea of taking on this project.

What I'm looking for is the mark-up dimensions to complete this as well as the exact locations of where the certain cross members need to be relocated. I have a certified pressure welder who is planning to help me to ensure the welds are good, plus I was planning on doing the "Step Cut" method and to box the frame to help add strength and make the re-assembly go smoother.

I know that 12" needs to come out of the centre of the frame and another 8" removed from the rear, but any specific locations of cuts would be much appreciated, as well as pictures from anyone who has down this in the past.
 

AuroraGirl

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Whats the length from the back of the cab squared on the frame to the termination of the frame rails? Im not a fan of cutting a frame up.. personally.. but I am curious what one of my frames are, but a cab is in the way of measuring front to back.
 

Matt69olds

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There are already several threads with this info.

And prepare for the haters...


Am I missing something? Why would there be haters worked up about a short bed conversion?
 

Scott91370

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Am I missing something? Why would there be haters worked up about a short bed conversion?
Some see it as ruining a good truck. Personally I don't mind. I was going to do it to one of them I have but then found a good enough price on a SWB so now I'll just sell the LWB.
 

MikeB

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Google "square body short bed conversion" and you'll get a ton of hits. Several years ago one of the vendors sold a kit for 67-72 trucks that included pieces to reinforce the fame at the cuts, as well as drawings and dimensions for frame and bed. I'm not sure, but there might be something similar available for 73-87.
 

Bennyt

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I know of two companies that make kits for square body. Metalox and built by brooks. Both are relatively inexpensive. I used the BxB kit as the metalox kit wasn't available last year when I did ours. Very easy 2-3 hours of cutting and welding. Metalox does probably a couple a month at his shop including shortening the bedsides. If you look up the thread for my sons truck you can see pictures.

Btw, I believe it's 14 and 6 to be factory swb dimensions. I only did 5 as I wanted a little extra frame but I think the minimum it 4. And the LWB frame is superior as it has an extra crossmember and 56" springs which ride better than the 52" swb.
 

bucket

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I know of two companies that make kits for square body. Metalox and built by brooks. Both are relatively inexpensive. I used the BxB kit as the metalox kit wasn't available last year when I did ours. Very easy 2-3 hours of cutting and welding. Metalox does probably a couple a month at his shop including shortening the bedsides. If you look up the thread for my sons truck you can see pictures.

Btw, I believe it's 14 and 6 to be factory swb dimensions. I only did 5 as I wanted a little extra frame but I think the minimum it 4. And the LWB frame is superior as it has an extra crossmember and 56" springs which ride better than the 52" swb.

The extra crossmember being the one for the carrier bearing?

Many many long bed trucks did not get the 56" rear springs.
 

AuroraGirl

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The extra crossmember being the one for the carrier bearing?

Many many long bed trucks did not get the 56" rear springs.
But the mounts are there, I believe. Is 56 inches the length from outer edge to outer edge on the actual spring on the longer side(toward truck) ?
 

AuroraGirl

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I know of two companies that make kits for square body. Metalox and built by brooks. Both are relatively inexpensive. I used the BxB kit as the metalox kit wasn't available last year when I did ours. Very easy 2-3 hours of cutting and welding. Metalox does probably a couple a month at his shop including shortening the bedsides. If you look up the thread for my sons truck you can see pictures.

Btw, I believe it's 14 and 6 to be factory swb dimensions. I only did 5 as I wanted a little extra frame but I think the minimum it 4. And the LWB frame is superior as it has an extra crossmember and 56" springs which ride better than the 52" swb.
14 and 6? Like... what do you mean?
 

AuroraGirl

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400(?), 350
I know of two companies that make kits for square body. Metalox and built by brooks. Both are relatively inexpensive. I used the BxB kit as the metalox kit wasn't available last year when I did ours. Very easy 2-3 hours of cutting and welding. Metalox does probably a couple a month at his shop including shortening the bedsides. If you look up the thread for my sons truck you can see pictures.

Btw, I believe it's 14 and 6 to be factory swb dimensions. I only did 5 as I wanted a little extra frame but I think the minimum it 4. And the LWB frame is superior as it has an extra crossmember and 56" springs which ride better than the 52" swb.
14 and 6? Like... what do you mean?
 

bucket

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But the mounts are there, I believe. Is 56 inches the length from outer edge to outer edge on the actual spring on the longer side(toward truck) ?

Mounts are the same, the rear hanger just gets mounted to the frame in a different set of holes.

56" from spring eye to spring eye, along the arch. The shorter springs are 52".
 

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