C20 to K20 conversion questions

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kmc_hauls

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Hey Chevy people, new here, posted an introduction and pics of my Cow the other day....now to actual tech questions.
I bought a complete Dana 44 with steering and springs as well as a 4x4 crossmember and motor mount brackets. 1st question for anyone who has done this conversion before, do any of the factory 2wd crossmember mounting holes in the frame line up with the 4x4 crossmember just to locate it properly (I expect to have to drill some holes but want to make sure it's located properly before drilling my frame).??
2nd question: on all of the crossover steering kits I find say you need at least a 2 inch or 2.5 inch lift to work with crossover steering...from looking at everything, measuring components and calculating I think the issue is the pitman arm and tie rod end are too bulky....has anyone tried using the stock 2wd pitman arm with the built in ball joint, cutting the stock 2wd tie rod and threading it and then making a d.o.m. thread on crossover bar?? It looks like it would be more compact...ideas? I like to run stock height but hate the push pull steering
 

Strick

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First, welcome to the site. If you have a 4x4 donor frame it will help tremendously with your swap. The entire crossmember must be changed along with the radiator/spring supports. The Crew frame is taller than the regular cab 10 & 20 stuff as well. You will want to source your donor from a K30.
I still have not done the swap on my C20 Crew and am kinda hesitant as my dad bought it new and it has over 400K miles as a 2WD log truck. My dad needed a 4x4 as bad as anyone but he would not pony-up and pay for it. Anyway, look on ORU and ORD for some ideas on the swap as well. Maybe you'll find more information than what I've been able to give.

Strickland
 

kmc_hauls

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Thanks Strick. I already have a crossmember and motor mount brackets from a 4x4...NO DONOR frames anywhere near me...Ive been watching all of the offerups/craigslists/facespace etc..
As far as the core support/spring mount, I will fab my own of those. Very simple piece. I want them heavier duty than the stamped sheet metal of the OE. I have some 1/4" plate and 3/8" plate. I am designing them with 2 sets of hole so if I don't like the stock spring ride I can swap to a set of rear 56" springs that have the 26" spring mount pin...so my mount will have one hole at stock position for the 47" springs with the centered pin at 23.5" and a forward hole 2.5 inches forward. Then all I have to do is move the shackle bracket back 6.5 inches and hopefully improve my ride if need be.
 

Strick

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K30 frames are difficult to source regardless of demographic, I feel your pain there.

Strickland
 

bucket

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If you build your front spring hangers to position the springs about 1" lower (which would increase ride height) then it will be easier to gain shackle/frame clearance with the taller C30 frame, without hurting castor angle.

That K10/20 crossmember is probably going to need a good bit of work to fit the C30 frame. If you are making your own hangers, the crossmember should be perfectly doable too.
 

kmc_hauls

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Thanks bucket and strick.....starting so fab this morning....been in Texas all week visiting grandkids....back to work
 

Raybob9289

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Nephew shared a FB marketplace add with me on Friday. 4 door K30 frame and cab with title for $350. I've done the conversion and I can't agree with te other fellas enough. Its way better to find a frame.
 

scrap--metal

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I've done the conversion and I can't agree with te other fellas enough. Its way better to find a frame.
I remembered your conversion and looked up that thread to confirm it was you. Did you replace the modified 2wd frame under your dually with a 4x4 frame like you planned?

@kmc_hauls, take @Raybob9289 first hand advice. Or plan for a lift to build some clearance between the engine crossmember and the front axle.
 

kmc_hauls

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No way....no $350 frame and cab anywhere near So Cal.....can't even find square bodies in wrecking yards here....people who don't live here have no idea what CA emissions laws have done to classic cars and trucks market here....it either costs 20x what it's really worth or it pays about $3000 to scrap it....not for resale parts....if you scrap it for emissions they can not sell a single part of of it here
 

kmc_hauls

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Besides....this truck is a family heirloom so I want to keep as much as possible original....swapping is not that hard....I've done a few conversions on other vehicles...
 

Big Ray

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I've seen it done. Easiest way is using the ORD engine crosmember, 4x4 engine mounts and spring mounts.
ORD FUSH rear front spring mount to mount the front springs.

Skye manufacturing makes a kit also, it has in a 6" lift built in to it.

I have a c20 burb in thinking of doing it to.
 

bucket

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I've seen it done. Easiest way is using the ORD engine crosmember, 4x4 engine mounts and spring mounts.
ORD FUSH rear front spring mount to mount the front springs.

Skye manufacturing makes a kit also, it has in a 6" lift built in to it.

I have a c20 burb in thinking of doing it to.

I've been meaning to do the swap with my '78 C20 Burb for years now. I've got a factory crossmember, mounts and hangers as well as a host of ORD parts. Engine crossmember, FUSH's, D60 crossover steering setup, b52 front hangers and all sorts of stuff gathered up for the swap. Whenever I finally get around to it, I plan to completely document the swap every step of the way. And show why some options may be better than others for the intended use.

The truck is getting to the point that it could use all new brakes and the front suspension needs rebuilt, so maybe the swap will actually happen this year.
 

Big Ray

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I've been meaning to do the swap with my '78 C20 Burb for years now. I've got a factory crossmember, mounts and hangers as well as a host of ORD parts. Engine crossmember, FUSH's, D60 crossover steering setup, b52 front hangers and all sorts of stuff gathered up for the swap. Whenever I finally get around to it, I plan to completely document the swap every step of the way. And show why some options may be better than others for the intended use.

The truck is getting to the point that it could use all new brakes and the front suspension needs rebuilt, so maybe the swap will actually happen this year.
If you do it document it here! I'll do the same.
 

Raybob9289

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I remembered your conversion and looked up that thread to confirm it was you. Did you replace the modified 2wd frame under your dually with a 4x4 frame like you planned?

@kmc_hauls, take @Raybob9289 first hand advice. Or plan for a lift to build some clearance between the engine crossmember and the front axle.
Working on it now
 

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