2WD to 4x4 conversion?

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shiftpro

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Which one is the cheaper way to go?


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I can't answer that. Depends on a price for 4x4 chassis. If you go with a B52 kit, you still need rear springs. Finding them in a junk yard is a gamblke because good chances they have been worked and are worn or sacked. You would need longer shocks, and good shocks cost more. Shocks are like,
you get what you pay for.
Another big hurdle is to convert to cross-over steering which I'm not convinced is absolutely necessary depending on use. If you rrally want to use the travel and flex afforded with 52" springs, then cross over is the only way to go.

I feel your best bet is to remain patient and vigilant for a cheap 4x4 chassis. I have seen completely rusted out trucks with a good frame and also.. visa versa, good cab and body but frame is a mess.
 
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I can't answer that. Depends on a price for 4x4 chassis. If you go with a B52 kit, you still need rear springs. Finding them in a junk yard is a gamblke because good chances they have been worked and are worn or sacked. You would need longer shocks, and good shocks cost more. Shocks are like,
you get what you pay for.
Another big hurdle is to convert to cross-over steering which I'm not convinced is absolutely necessary depending on use. If you rrally want to use the travel and flex afforded with 52" springs, then cross over is the only way to go.

I feel your best bet is to remain patient and vigilant for a cheap 4x4 chassis. I have seen completely rusted out trucks with a good frame and also.. visa versa, good cab and body but frame is a mess.
My 4x4 will not use all the travel of the springs and what not. Just used as way to drive in the snow or in the fields and what not


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shiftpro

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[emoji23] I’m in Illinois so just about everyone who had one at some point is now rusted out because of the salt they put on the roads. Ain’t very many Fords here either,[emoji2369] but maybe I also have Ford Blindness syndrome


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I grew up in Villa Park, '63 - '73. Born in Canada 1960.
 

shiftpro

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My 4x4 will not use all the travel of the springs and what not. Just used as way to drive in the snow or in the fields and what not


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I get that but I still think you're best off to find another truck. That B52 conversion is much more than just a bolt on an go. Lot's of farting around and as i mentioned before, often guys find they need to trim and adjust the front brackets. I think best to leave this setup for those who want and need massive travel.
Other problems to loo out for with a 52" front spring... often when using an old used spring set, they are TOO squishy on the highway and then a custom
swaybar LINK needs to be made. A fresh set of rear springs will be tight enough that this will not be an issue. but then you're buying new and another handful of $100 bills is gone.
 

kickdeez

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I can't speak specifically to the pickup truck frames, but the suburban frames definitely differ from 2wd to 4wd. You are probably best served by looking into the companies that have been previously suggested: Offroad Design and DIY4X. Also take a look at Cut Brothers, LLC. They have not been producing as much product as they used to, but they have made some pretty slick 4wd conversion parts for squarebody trucks.

You will need to source the following frame-related parts:
Motor mounts and engine cradle/crossmember that work with each other. (I can tell you that on the suburbans you cannot just bolt 4wd motor mount brackets into a 2wd frame channel. The frame heights differ in this spot. I assume the pickup frames are similar.)
Front spring hanger
Shackle kit
Depending on your desired transmission/transfer case combo, you may need a different transmission crossmember

Other items:
Front springs
Front axle
Front shocks
Crossover steering kit for front axle (or steering box from 4wd to retain push/pull steering)
Transmission and transfer case combo
Front driveshaft
Rear driveshaft will need to be modified
Front brake lines will likely need to be lengthened
Exhaust re-worked
Transmission tunnel hacked, raised, or otherwise modified

There are probably a few other components I have not captured in this list. Also, depending on how you do your front spring hanger and shackles, you may end up with a taller front suspension than your factory rear suspension, requiring you to lift the rear to match.
 
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I can't speak specifically to the pickup truck frames, but the suburban frames definitely differ from 2wd to 4wd. You are probably best served by looking into the companies that have been previously suggested: Offroad Design and DIY4X. Also take a look at Cut Brothers, LLC. They have not been producing as much product as they used to, but they have made some pretty slick 4wd conversion parts for squarebody trucks.

You will need to source the following frame-related parts:
Motor mounts and engine cradle/crossmember that work with each other. (I can tell you that on the suburbans you cannot just bolt 4wd motor mount brackets into a 2wd frame channel. The frame heights differ in this spot. I assume the pickup frames are similar.)
Front spring hanger
Shackle kit
Depending on your desired transmission/transfer case combo, you may need a different transmission crossmember

Other items:
Front springs
Front axle
Front shocks
Crossover steering kit for front axle (or steering box from 4wd to retain push/pull steering)
Transmission and transfer case combo
Front driveshaft
Rear driveshaft will need to be modified
Front brake lines will likely need to be lengthened
Exhaust re-worked
Transmission tunnel hacked, raised, or otherwise modified

There are probably a few other components I have not captured in this list. Also, depending on how you do your front spring hanger and shackles, you may end up with a taller front suspension than your factory rear suspension, requiring you to lift the rear to match.
Thanks


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I get that but I still think you're best off to find another truck. That B52 conversion is much more than just a bolt on an go. Lot's of farting around and as i mentioned before, often guys find they need to trim and adjust the front brackets. I think best to leave this setup for those who want and need massive travel.
Other problems to loo out for with a 52" front spring... often when using an old used spring set, they are TOO squishy on the highway and then a custom
swaybar LINK needs to be made. A fresh set of rear springs will be tight enough that this will not be an issue. but then you're buying new and another handful of $100 bills is gone.
Thanks


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So from what you guys have been saying, a frame swap with a donor truck will be best


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I grew up in Villa Park, '63 - '73. Born in Canada 1960.

'Nother Illini here. I thought it was normal for cars to rust to **** in 10 years when I was a little kid. Until we took a couple long trips out west, down south and I realized what the rust belt was.
 
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'Nother Illini here. I thought it was normal for cars to rust to **** in 10 years when I was a little kid. Until we took a couple long trips out west, down south and I realized what the rust belt was.
Same man, going to Oregon seeing so many vehicles running pre 1995 and them chugging along without you being able to see through the floor panels and what not. What’s crazy is the prices are the same, you can get a rusted out Toyota pickup for 5,000 and in other states get one that’s not rusted out for the same price!


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Salty Crusty

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This one was a surprise to me. I was at a buddy's shop and a friend of his brought his father in law to look at some wheels. I was visiting with the guy and he mentioned that he had a 4WD Suburban that he wanted to sell for $3K. I thought to myself that I knew what a $3000 suburban looked like but decided to look at it anyway. I rolled under it, took it for a drive and shook the guy's hand. It never hit the market, he just shot off a price and I snagged it.
We do have a lot of nice squares here in Texas. I only paid $300 for the straight '91 that I'm going to put on the '84 frame. Someone had pulled the TBI engine and never got around to putting it back in and his wife wanted to get it out of the way.
I try to keep enough cash on hand to be able to take advantage of these things when they come up. Just gotta be patient but ready to jump at the drop of a hat.
 

Grit dog

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This one was a surprise to me. I was at a buddy's shop and a friend of his brought his father in law to look at some wheels. I was visiting with the guy and he mentioned that he had a 4WD Suburban that he wanted to sell for $3K. I thought to myself that I knew what a $3000 suburban looked like but decided to look at it anyway. I rolled under it, took it for a drive and shook the guy's hand. It never hit the market, he just shot off a price and I snagged it.
We do have a lot of nice squares here in Texas. I only paid $300 for the straight '91 that I'm going to put on the '84 frame. Someone had pulled the TBI engine and never got around to putting it back in and his wife wanted to get it out of the way.
I try to keep enough cash on hand to be able to take advantage of these things when they come up. Just gotta be patient but ready to jump at the drop of a hat.
Ho Lee Schitt! It's 4wd too? Wow!

Well, there's a reason Gas Monkey Garage aint in Iowa. They'd be Rust Donkey Garage up there. Not as appealing!
 

bucket

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Who is the other guy here that insisted you could bolt the suspension of a 4x onto a 2x frame? He wanted to argue with me and posted pictures
of a 2x frame with zero clearance for the rear shackle to move.

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.
 

pontiac6269

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I did this conversion to my 81 C20. The videos start out with me replacing the cab corners and rockers on the passenger side. I started the conversion about the middle of the summer (2019) and had the front done in December. I put a plow on it to plow my driveway, got that installed and working for the first big snow storm. I changed the rear spring hangers last summer (2020). Bought a rusted out 79 K20 to get the trans(turbo 400), transfer case(203 that was converted to part time), plow and any thing else. My spring hangers came from 78 K20 frame I bought from a salvage yard 4 years ago to get the full floater 14 bolt(4.10 gears) and I also kept the matching Dana 44.
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