K10 to C20 frame

[bucket]

This topic has been covered many times here before and there's a lot of good info to be read. But the short answer is... Yes it can be done, no it's not easy, no the holes are not already in the frame, yes it involves custom work, and it may or may not be worth the trouble.

Why not just build the K10?

 

[bucket]

Here's a few with some good info sprinkled throughout.

2wd to 4wd conversion

This topic has probably been pounded to death but here it is again. I was planning on building a 3/4 ton 4wd pick up from the ground up. I just got the axles under the chassis and got it rolling. . The body was shot, the only donor truck I could find with a decent cab was an 86 1 ton dually...

www.gmsquarebody.com

2WD to 4x4 conversion?

To make a c20 to a k20 do you have to do a frame swap? Or just suspension, transmission and drivetrain? Sent from my iPhone using Tapatalk

www.gmsquarebody.com

https://www.gmsquarebody.com/threads/1974-2wd-crew-to-4x4.21778/

Gotta tag my ol buddy @shiftpro on this one. My guess is we will finally agree in the case of this truck.

 

[shiftpro]

Here's a few with some good info sprinkled throughout.

2wd to 4wd conversion

This topic has probably been pounded to death but here it is again. I was planning on building a 3/4 ton 4wd pick up from the ground up. I just got the axles under the chassis and got it rolling. . The body was shot, the only donor truck I could find with a decent cab was an 86 1 ton dually...

www.gmsquarebody.com

2WD to 4x4 conversion?

To make a c20 to a k20 do you have to do a frame swap? Or just suspension, transmission and drivetrain? Sent from my iPhone using Tapatalk

www.gmsquarebody.com

https://www.gmsquarebody.com/threads/1974-2wd-crew-to-4x4.21778/

Gotta tag my ol buddy @shiftpro on this one. My guess is we will finally agree in the case of this truck.

Thanks I'll check it out.

 

[shiftpro]

Here's a few with some good info sprinkled throughout.

2wd to 4wd conversion

This topic has probably been pounded to death but here it is again. I was planning on building a 3/4 ton 4wd pick up from the ground up. I just got the axles under the chassis and got it rolling. . The body was shot, the only donor truck I could find with a decent cab was an 86 1 ton dually...

www.gmsquarebody.com

2WD to 4x4 conversion?

To make a c20 to a k20 do you have to do a frame swap? Or just suspension, transmission and drivetrain? Sent from my iPhone using Tapatalk

www.gmsquarebody.com

https://www.gmsquarebody.com/threads/1974-2wd-crew-to-4x4.21778/

Gotta tag my ol buddy @shiftpro on this one. My guess is we will finally agree in the case of this truck.

https://www.gmsquarebody.com/threads/1974-2wd-crew-to-4x4.21778/

In this build he hung a 52s under the front end with a B52 kit. This is what I have been saying all along.. if you want a big lift AND wheel travel then go with a B52 kit.
Otherwise if you hang a 4x front end on your 2wd, you're stuck with the flat stock springs, which I wasn't aware of earlier. Any lift springs, when the arch is compressed, WILL bang into the frame behind the rear hangers. I saw a photo once where the guy cut a notch in the frame for spring eye clearance... not ideal by any means. The notch can be plated and reinforced from the inside... but if a vehicle inspector sees this it would make for a bad and expensive day.
One ton 2x/4x frames are NOT the same, so there is a serious compromise to be considered.

It's doing a disservice to say you can just unbolt the 4x front end and mount it on the 2x frame. Yes it's possible. I would never go through all that work to have to settle for stock crappy springs imo.

One could shim the front spring mount off the frame, to effectively lower it, raising the ride height. The the rear shackle would need to be made longer... is that a good idea? The longer a shackle is the less lateral strength.

 

[bucket]

https://www.gmsquarebody.com/threads/1974-2wd-crew-to-4x4.21778/

In this build he hung a 52s under the front end with a B52 kit. This is what I have been saying all along.. if you want a big lift AND wheel travel then go with a B52 kit.
Otherwise if you hang a 4x front end on your 2wd, you're stuck with the flat stock springs, which I wasn't aware of earlier. Any lift springs, when the arch is compressed, WILL bang into the frame behind the rear hangers. I saw a photo once where the guy cut a notch in the frame for spring eye clearance... not ideal by any means. The notch can be plated and reinforced from the inside... but if a vehicle inspector sees this it would make for a bad and expensive day.
One ton 2x/4x frames are NOT the same, so there is a serious compromise to be considered.

It's doing a disservice to say you can just unbolt the 4x front end and mount it on the 2x frame. Yes it's possible. I would never go through all that work to have to settle for stock crappy springs imo.

One could shim the front spring mount off the frame, to effectively lower it, raising the ride height. The the rear shackle would need to be made longer... is that a good idea? The longer a shackle is the less lateral strength.

Those threads were posted just to save the OP some research digging. I just figured I'd bring it to your attention and agree with me that it doesn't make much sense for the OP to convert. You know, cause usually it's me saying that it's worth the trouble and you saying it's not, lol.

As for the 1-ton frames, yes the curvature is different. But with proper spring hanger placement and slightly longer (and beefier) shackles, it's perfectly doable and you get full travel with your lift springs. Guys have done it. It ends up adding about 1" in height, which isn't much compared to the B52 route.

 

[shiftpro]

Those threads were posted just to save the OP some research digging. I just figured I'd bring it to your attention and agree with me that it doesn't make much sense for the OP to convert. You know, cause usually it's me saying that it's worth the trouble and you saying it's not, lol.

As for the 1-ton frames, yes the curvature is different. But with proper spring hanger placement and slightly longer (and beefier) shackles, it's perfectly doable and you get full travel with your lift springs. Guys have done it. It ends up adding about 1" in height, which isn't much compared to the B52 route.

I appreciate your position bucker.

Longer shackles...? do you mean longer than the .5" longer shacks that the mid 80s K30s started using? Or a common mod for any of
our square 4xs.. as we also discovered the geometry likes that little extra trail provided by tipping the diff back a bit. Even so much that the extra angle on the driveshaft is still worth it.

Ok so we're going to need longer than what I just described right? Ok now the diff is pointing back too much. Too much trail and too much angle on the front U joint. Now that can of worms is either shimming the diff forward again or shimming the front hanger down.

Seem totally doable to me. Hmm.

What am I missing? Certainly not the horse haha.

 

[Phil 83K20]

I’m thinking if you did a new VIN, it’d then be subject to 2022 CA emissions standards.
So unless you wanna do a Tesla swap…

 

[shiftpro]

Those threads were posted just to save the OP some research digging. I just figured I'd bring it to your attention and agree with me that it doesn't make much sense for the OP to convert. You know, cause usually it's me saying that it's worth the trouble and you saying it's not, lol.

As for the 1-ton frames, yes the curvature is different. But with proper spring hanger placement and slightly longer (and beefier) shackles, it's perfectly doable and you get full travel with your lift springs. Guys have done it. It ends up adding about 1" in height, which isn't much compared to the B52 route.

I appreciate your position bucker.

Longer shackles...? do you mean longer than the .5" longer shacks that the mid 80s K30s started using? Or a common mod for any of
our square 4xs.. as we also discovered the geometry likes that little extra trail provided by tipping the diff back a bit. Even so much that the extra angle on the driveshaft is still worth it.

Ok so we're going to need longer than what I just described right? Ok now the diff is pointing back too much. Too much trail and too much angle on the front U joint. Now that can of worms is either shimming the diff forward again or shimming the front hanger down.

Seem totally doable to me. Hmm.

What am I missing?

My guess is we will finally agree in the case of this truck.

There must be something we can argue over?
I'm running out of ideas here..

 

[bucket]

I appreciate your position bucker.

Longer shackles...? do you mean longer than the .5" longer shacks that the mid 80s K30s started using? Or a common mod for any of
our square 4xs.. as we also discovered the geometry likes that little extra trail provided by tipping the diff back a bit. Even so much that the extra angle on the driveshaft is still worth it.

Ok so we're going to need longer than what I just described right? Ok now the diff is pointing back too much. Too much trail and too much angle on the front U joint. Now that can of worms is either shimming the diff forward again or shimming the front hanger down.

Seem totally doable to me. Hmm.

What am I missing?


There must be something we can argue over?
I'm running out of ideas here..

I'm talking the 1/2 longer ones like the '87-ish and later squares. I've seen it done and it can clear. But a lot has to do with the springs too, regarding bushing size and main leaf thickness.

Can we argue about pinion shims? I've got no problems with them as long as they bolt into the pack. Especially if they are steel. Many lift springs come with shims to point the pinion up anyway.

 

[shiftpro]

I'm talking the 1/2 longer ones like the '87-ish and later squares. I've seen it done and it can clear. But a lot has to do with the springs too, regarding bushing size and main leaf thickness.

Can we argue about pinion shims? I've got no problems with them as long as they bolt into the pack. Especially if they are steel. Many lift springs come with shims to point the pinion up anyway.

I have part of a pinion shim in my splitting maul handle.

 

[ptrckdillard]

wouldnt it be a legaler and also safer in his situation to get the vehicle titled with a new vin so it would be a 2022 or 2021(whenever) with a new VIN attached model year from the california gestapo.

The way CA wants it is, proof of ownership of both vehicles.
Then they want you to swap the 78 cab onto the 73 frame.
They’ll then attach the 78 vin to the 73 title and scrap the 78.
This can be done legally with bill of sales, titles and a statement of facts.
There is one other form that needs to be filled out I believe it’s form 256.
It’s pretty simple to do.
I just hate the fact that they push the destruction of the “parts” vehicle.

I'm not concerned on the frame numbers matching, it's sort of irrelevant due to the VIN not belonging to a K series anyway. Which is why I found a 73-75 truck and it makes the swapping of VIN's around also irrelevant. Also, using the 73-75 as a "donor" title circumvents the need for a VIN inspection which is the only way the frame VIN and body VIN becomes an issue. But just in case, the VIN on the 79 is already removed and the VIN is not in the system anymore.

I'm really just wanting to know, if I can bolt the rear and front springs/shocks onto the long bed frame? Are the frame rails pre-drilled for K or C series 20 or 10 from the factory, and they are assembled as designated in the plant?

Again, thanks for all the input, and Uncle Jack's a weird dude!!!

 

[AuroraGirl]

I'm not concerned on the frame numbers matching, it's sort of irrelevant due to the VIN not belonging to a K series anyway. Which is why I found a 73-75 truck and it makes the swapping of VIN's around also irrelevant. Also, using the 73-75 as a "donor" title circumvents the need for a VIN inspection which is the only way the frame VIN and body VIN becomes an issue. But just in case, the VIN on the 79 is already removed and the VIN is not in the system anymore.

I'm really just wanting to know, if I can bolt the rear and front springs/shocks onto the long bed frame? Are the frame rails pre-drilled for K or C series 20 or 10 from the factory, and they are assembled as designated in the plant?

Again, thanks for all the input, and Uncle Jack's a weird dude!!!

i dont think california is worried about the vin being 2wd truck when yours is 4wd much more than we were talking about th title, dash, frame having the same vin

 

[ptrckdillard]

wouldnt it be a legaler and also safer in his situation to get the vehicle titled with a new vin so it would be a 2022 or 2021(whenever) with a new VIN attached model year from the california gestapo.

The big issue we Commiefornians face is any vehicle 1976 or newer has to adhere to the smog laws. If you register it as a "whatever" year newer than 76, I also believes it is no longer registered as a Chevy, but as a special construction title.

 

[AuroraGirl]

I'm not concerned on the frame numbers matching, it's sort of irrelevant due to the VIN not belonging to a K series anyway. Which is why I found a 73-75 truck and it makes the swapping of VIN's around also irrelevant. Also, using the 73-75 as a "donor" title circumvents the need for a VIN inspection which is the only way the frame VIN and body VIN becomes an issue. But just in case, the VIN on the 79 is already removed and the VIN is not in the system anymore.

I'm really just wanting to know, if I can bolt the rear and front springs/shocks onto the long bed frame? Are the frame rails pre-drilled for K or C series 20 or 10 from the factory, and they are assembled as designated in the plant?

Again, thanks for all the input, and Uncle Jack's a weird dude!!!

shouldnt up to 80 be a VIN inspection exception or is california not worry about pre 76 vehicles

EDIT: you answered in the lick of time between my asking lol

 

[ptrckdillard]

i dont think california is worried about the vin being 2wd truck when yours is 4wd much more than we were talking about th title, dash, frame having the same vin

Technically it could matter, but it's done all the time. You would run into trouble if your frame VIN was off a reported stolen vehicle or also if you were involved in a major injury/fatal crash and the vehicle is inspected by LE. You could incur liability and lack of vehicle malfunction defense (if that were the case) in the event of a that type of incident. But like I said, I'm not too worried about that.