1982 LWB to SWB Conversion

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AuroraGirl

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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".
Oh okay, so not straight across but following the arch? I know my truck and trailer have 56. my frame I think has 56. But the 1/2 ton im guessing is 52
 

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Oh okay, so not straight across but following the arch? I know my truck and trailer have 56. my frame I think has 56. But the 1/2 ton im guessing is 52

It's a pretty close measurement either way. It gets confusing with lift springs because by the time you measure along the bigger arch, it adds length. So it actually measures longer than the spring it replaces.
 

AuroraGirl

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It's a pretty close measurement either way. It gets confusing with lift springs because by the time you measure along the bigger arch, it adds length. So it actually measures longer than the spring it replaces.
Very true, I forgot to even consider that, the distance unsprung eye to eye is more important for fitment, yes? As you wouldnt want to pull the spring the wrong direction to fit, that sounds like a recipe for disaster. Center of eye to center of eye?
 

Matt69olds

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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.


I don’t think it ruins the truck, it just makes a good truck better.
 

Matt69olds

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Thanks, the Olds is my “relaxation”. Have a bad day? A drive in the Olds puts me in a better mood. Ain’t no feelin’ like Oldsmobiling!!


As for the long bed/short bed debate, no question a long bed is more useful. Full sheets of plywood? No problem with a long bed! I use my dads long bed GMC when I get firewood. The tree service place charged by the truckload. Obviously, you can fit more wood in a long bed!! The GMC also sits much lower, making loading/unload that wood easier My Ram is a short bed, when I need plywood I use ratchet straps to keep things from sliding out. Most people would agree a short bed truck looks sporty compared to the long bed.
 

AuroraGirl

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Thanks, the Olds is my “relaxation”. Have a bad day? A drive in the Olds puts me in a better mood. Ain’t no feelin’ like Oldsmobiling!!


As for the long bed/short bed debate, no question a long bed is more useful. Full sheets of plywood? No problem with a long bed! I use my dads long bed GMC when I get firewood. The tree service place charged by the truckload. Obviously, you can fit more wood in a long bed!! The GMC also sits much lower, making loading/unload that wood easier My Ram is a short bed, when I need plywood I use ratchet straps to keep things from sliding out. Most people would agree a short bed truck looks sporty compared to the long bed.
Rocketing to new heights, as always :)

We are the heirs of a spiritual tradition. I currently own a 1978, 1980 Cutlass Supreme, a 1990 88, and a 1999 Aurora. I formerly owned a 2001 Aurora and 88 Cutlass Calais.

Now, I wish any of them were on the road at the moment :(
 

TPISly-C10

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iv done this cut on mine was easy and cheap to do...and if you are lucky like me and find a short bed at a decent price..your be ok!

if you can watch Motor Trend app and see Carfix season 1 episode 4 they all explain verry well how to..this is the place i find all my info and mesurement...for my truck i use the same technique as the Brother truck kit for 67-72 truck with a "C" chanel inforcement bolted and welded! ;)

here a short view of CarFix episode find on youtube! :)

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TPISly-C10

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and i forgot to mention....if you have 56" long leaf spring like mine your be ok to clear the bed frame without have to notch! :)

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Scott91370

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RoryH19

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Here's a page: http://www.73-87.com/7387garage/chassis_suspension/lwb_to_swb.htm

I like the step cut mentioned here: https://www.gwellwood.com/project-cars/the-crusty-chevy/shortboxing-the-frame/


Admins, if this link is not allow I get it (worth a try though)
This one has other links inside it to other builds as well: http://forum.73-87chevytrucks.com/smforum/index.php?topic=35447.0
Agreed, I would use the step method as well.
Provides more strength than just a straight cut.
Of course with backing plates, bolts and welding the straight will be very strong.
 

Bennyt

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Here are the instructions that came with our kit from Built by Brooks. Metaloxfab.com brackets are simpler and less expensive.
 

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Bennyt

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Here it is welded in but not all the holes drilled yet for bolts.
 

AuroraGirl

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I wonder if anyone has ever taken a short bed conversion frame rail piece and made a long bed?>
 

Salty Crusty

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Not to throw fuel on a fire, but one of the main benefits of a long bed is how much better they are with a trailer hooked up. Much more stable on the road.
But....easier to back where you want it with a shortie.
So it's still 6 of one, half dozen of the other.
Or as a good friend of mine used to say, "On the other hand....you have other fingers"
 

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