2WD to 4x4 conversion?

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Ricko1966

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Correct me if I'm wrong, but if he insists on doing a 4x4 conversion, couldn't he even use a k10 frame and running gear which should be much easier to find. Then just source 3/4 ton diffs, and springs. I think they are the same frame.
 

shiftpro

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Lol, that was me. You should probably go look at those pictures again. That was the tall C30 frame with stock type springs so the shackle didn't need to move in that direction. Your average lift spring is going to put the shackle at a different angle and provide more clearance. A factory K30 also has very little shackle clearance. And I'll point out once again, the 10/20 frames are contoured differently than the 30 series frames and there is no clearance issues whatsoever when installing shackles in the correct location, other than having to relocate the parking brake cable and trim some width off the lower frame lip.

But anyway, none of that needs to carry on here because I agree that in this case, a frame swap is definitely the better option.

To be clear the men I have held in my lap while they cried (twice) were trying this with C20s, not C30s. So I don't know or have considered this on a one ton.
And yes the stock flat springs (convex after a few miles down the road from the dealership) would not move the shackle backwards.But to go through all that work to run stock flat springs...!?

Anyway, you have inspired me to consider this with Big Blue<<< my avatar. My 4x4 crew cab frame I have is a rusted mess on the rear, while Blue is
immaculate. Comes with a 2x steering box ready and willing for cross over!
 

shiftpro

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Correct me if I'm wrong, but if he insists on doing a 4x4 conversion, couldn't he even use a k10 frame and running gear which should be much easier to find. Then just source 3/4 ton diffs, and springs. I think they are the same frame.
The 20 frame is a slightly thicker metal and he wants to haul. Other than that they are the same as well the front diff is also the same. Rear on a 10 is a ...
10 bolt. UNLESS it's a Heavy Half or Big Ten then they MIGHT have the 14 bolt.
Also have to watch out for K20swith the 9" semi floater... it's strong but if you're going to pack around that weight it may as well be the 10.5 14 bolt we all love.
 

RecklessWOT

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^ you would have a cat if you saw the time capsule '83 that I bought about a month ago. I have to replace the cracked dash, just happen to have one I salvaged years ago.
Fresh paint, perfect seats, 60K on engine rebuild, 40K on trans rebuild, new tires, garage kept the past 20 years and driven less than 7000 miles in that time period. Guy asked $3K, I couldn't even make myself offer $2999, this thing is a peach.
I already had the '91 2WD that I just bought the '84 4WD donor for but couldn't pass up the '83. I hope to send it to Loveland CO for the grandkids so they can actually get out into the mountains. That will leave this one for me to build as I want to.
Hah, small world. I bought my 'burb in Loveland
 

shiftpro

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Only difference is the front of the frame.2wd is coils,4WD is leaf springs.

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Nice pics btw...
 

Ricko1966

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The 20 frame is a slightly thicker metal and he wants to haul. Other than that they are the same as well the front diff is also the same. Rear on a 10 is a ...
10 bolt. UNLESS it's a Heavy Half or Big Ten then they MIGHT have the 14 bolt.
Also have to watch out for K20swith the 9" semi floater... it's strong but if you're going to pack around that weight it may as well be the 10.5 14 bolt we all love.

Are you sure? I thought the k10 and k20 frame were the same just different bolt ons frt diff, rear diff, etc. So after your post I hit it up on Google which funny enough lead me to a very informative post on this forumn from Feb 25th 2011 I do not know how to link to it, it was started by hotrodpc .it might do this guy some good to read it.

Since I couldn't link to it I posted to it hoping it shows up on today's posts.
 
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shiftpro

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Are you sure? I thought the k10 and k20 frame were the same just different bolt ons frt diff, rear diff, etc. So after your post I hit it up on Google which funny enough lead me to a very informative post on this forumn from Feb 25th 2011 I do not know how to link to it, it was started by hotrodpc .it might do this guy some good to read it.

Since I couldn't link to it I posted to it hoping it shows up on today's posts.
Digging in my memory hole, no I'm not sure. I've seen both sides of this argument though. Best I recall is the very slightly thicker rails. And then, there are all the micro and macro variations that appeared with no explanations lol.
 

bucket

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Digging in my memory hole, no I'm not sure. I've seen both sides of this argument though. Best I recall is the very slightly thicker rails. And then, there are all the micro and macro variations that appeared with no explanations lol.

I think it varied from year to year and between different models. The specifics are hard to nail down.
 
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I think it varied from year to year and between different models. The specifics are hard to nail down.
Dang


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Kilian

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When looking at the 7.003 section in the Chevy parts catalogs, 73-80 had the same frame assembly (or at least replacement assembly) for both 1/2 ton and 3/4 ton trucks. Gets little more confusing for 81 and up trying to decipher the PC info, at least for me.

Depending on how fast you want to get working on your project, patience is key. I've been thinking of doing a 4x4 conversion to my 2WD 3/4 ton truck and kept my eye out for a frame. Being in Wisconsin, I knew it was going to take a while to find a decent frame, but last fall I found one that is really good for $350...came with 14 bolt FF with limited slip in the rear as a bonus.
 

pontiac6269

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My 81 C20 frame was 3mm thicker then the 79 K20 frame and a 80s K10 frame, so not much difference.
 

80BrownK10

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My 81 C20 frame was 3mm thicker then the 79 K20 frame and a 80s K10 frame, so not much difference.
3mm of metal sounds pretty thick to me! When thinking how thick they are to begin with.
 

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