Another C to K conversion

[4x4_76]

I just had to pay membership to have acces to this forum

I started my Suburban project two weeks ago, haven't done much than just figuring out what I'm against with. That 'Burb has been in our barn for a few years now. My brother bought it and started fixing rusted sheetmetal. Interior was taken pieces, all the doors were strippe down etc. For some reason he lost his interest on it, so we towed it to the barn. Then the 'Burb served as a donor, lost both engine and tranny. And then it just sat there, waiting for something to happen. We tried to sell it, with no luck.

Three weeks ago I had an idea. Suburban is 2wd (no good), and I had a 6.2diesel, 700 tranny, two D44's, and a passion for 4x4's. Engine and tranny, and axle were left from my Blazer, that will be built for competition use. But that's whole other story. All these parts were also for sale, but maybe I had a too high price for them so no one was interested enough to buy them.

I was thinking that maybe I could make 4wd out of that 2wd, and I only need t-case and suspension, and all small parts. After a litlle searching, I found that I could use radius-arms from Land Rover. Panhard maybe from Dodge Ram, and Y-link steering from Ford. It will have x-over steering, but for now I'm using Ford stuff. That Dodge panhard isn't best sollution because it has huge curve because of the D60 pumpkin. Something more straight would be better, I'll check what Ford could offer. Land Rover panhard is too short.

It will have coils, but from where, that's to solved when I get everything else done. I have to fab new engine crossmember, that will also serve as a coil tower.

Pic will come after I get something done.

Couple of questions. Was the 235/85R16 tire optional on 1500-series Suburban? If it was, that means I could get legally 33" tires under the 'Burban. Yes, they are small, but law is the law, you can go 2" bigger tire than what was offered from the factory. Blazers had 31x10.5, but not 'Burbans. At least that was told on RPO code list.

About the RPO's, does Chevy and GMC share the same codes? I cross referenced RPO list on the glove department to the list I found from the web (Chevy list), and everything else matched, but the tires. Maybe there is differences in production years?

 

[GMCJason]

Sounds like quite a project.

I don't believe the 235/85R16 tire was offered on the 1/2 ton Suburban (this, however, would very likely depend on the model year.) For that it was the 235/85R15, which translates into a 30.7" diameter. Now, I won't proclaim to know anything about laws in Finland but I do know that almost no, if any, tire that claims to be 31" actually measures a full 31" in diameter; they would be more like 30.5" or so. That being said, adding the allowable 2" to the stock tire diamter would give you 32.7", which is about the actual size of an advertised 33" tire.

I'm pretty sure that GMC and Chevy share the same RPO codes.

Good luck,

Jason

 

[4x4_76]

Yeah, there is lot to do. I have to rust fix all the doors and a tailgate. Then put all the small parts together (easy to do when you haven't taken them off ), and paint it. Still figuring which one, gloss black, or mat. Maybe mat, 'cause it's going to be dirty anyway.

What comes to conversion, and radius arm brackets, I've been designing them in my head for almost two weeks. They are actually easy parts compared to crossmember/coil tower. I have basic desing of the towers in my head, but to get it done takes hours of fabrication.

One thing to add complexity is the t-case adapter. I don't wan't the t-case to hang under the frame rails, so I'm fabbing one that rotates it upward. Maybe little floorboard trimming is needed, that is to be seen when I get t-case. Which is going to be NP208. I have one 205, but is going to my Blazer.

I'm going to lift it 2"-3", and if I rotate t-case about 4" up, front d-shaft will see that as a 6"-7" lift. Guess that's in a limit, that I don't have to rotate pinion up?

About the tire sizes, here, when a car/truck is taken to safety inspection and you want to register bigger tires, inspector refers to STRO-manual, and for example 9.50-16.5LT is exactly 30,5" tall. 9.50-16.5LT was offered on 1981, if I read correctly from brochure that is available in here: http://brochures.slosh.com/ Pretty hard to read most of them, kind of blurry pics.

Oh well, I have to get some sleep, been awake for 18,5 hrs

 

[imiceman44]

Yeah, there is lot to do. I have to rust fix all the doors and a tailgate. Then put all the small parts together (easy to do when you haven't taken them off ), and paint it. Still figuring which one, gloss black, or mat. Maybe mat, 'cause it's going to be dirty anyway.

What comes to conversion, and radius arm brackets, I've been designing them in my head for almost two weeks. They are actually easy parts compared to crossmember/coil tower. I have basic desing of the towers in my head, but to get it done takes hours of fabrication.

One thing to add complexity is the t-case adapter. I don't wan't the t-case to hang under the frame rails, so I'm fabbing one that rotates it upward. Maybe little floorboard trimming is needed, that is to be seen when I get t-case. Which is going to be NP208. I have one 205, but is going to my Blazer.

I'm going to lift it 2"-3", and if I rotate t-case about 4" up, front d-shaft will see that as a 6"-7" lift. Guess that's in a limit, that I don't have to rotate pinion up?

About the tire sizes, here, when a car/truck is taken to safety inspection and you want to register bigger tires, inspector refers to STRO-manual, and for example 9.50-16.5LT is exactly 30,5" tall. 9.50-16.5LT was offered on 1981, if I read correctly from brochure that is available in here: http://brochures.slosh.com/ Pretty hard to read most of them, kind of blurry pics.

Oh well, I have to get some sleep, been awake for 18,5 hrs

Are you using the coil suspension because it's more available in Europe or because you want coils?
To do a 4x4 conversion on the suburban would be sooo easy of you went with leaf springs.
If you are doing it because it's nicer, then I would suggest to find the whole ford setup and adapt it, the radius arms, the buckets coils , everything and then just remove one bushing from one of the radius arms for better articulation.

As for the brochures, if you have trouble reading them, the guy that did that is a friend and he could probably get you a better picture if you tell me which one you need.
I think he did a medium quality to save space on the site.

Good luck and if there is anything we can help in as advise goes, keep the questions comming.

 

[4x4_76]

Are you using the coil suspension because it's more available in Europe or because you want coils?
To do a 4x4 conversion on the suburban would be sooo easy of you went with leaf springs.
If you are doing it because it's nicer, then I would suggest to find the whole ford setup and adapt it, the radius arms, the buckets coils , everything and then just remove one bushing from one of the radius arms for better articulation.

As for the brochures, if you have trouble reading them, the guy that did that is a friend and he could probably get you a better picture if you tell me which one you need.
I think he did a medium quality to save space on the site.

Good luck and if there is anything we can help in as advise goes, keep the questions comming.

I was first going to go Ford route, but when I asked them from one of our off-road shops, they told that Ford parts are hard to find, and suggested to use 130 Defender radius arms. And when I thought about it, it's true. There's hardly ever Ford truck parts for sale, even less 4x4 suspension parts.

And when it comes to front GAWR, there aren't much options. 130 Defender has enough to use it's parts under diesel powered Chevy. Other would have been Toyota 70-series rear arms.

Why I'm doing this? I have front spring hangers and engine crossmember from blazer (which will have 3-link w/panhard), but that would have been basicly bolt-on operation. Yes, I want coils, but even more it's a matter of design and build, to create something different

I will tell you what brochures I need, but it's closer to safety inspection. I need lots of documents to make things easy.

 

[imiceman44]

I was first going to go Ford route, but when I asked them from one of our off-road shops, they told that Ford parts are hard to find, and suggested to use 130 Defender radius arms. And when I thought about it, it's true. There's hardly ever Ford truck parts for sale, even less 4x4 suspension parts.

And when it comes to front GAWR, there aren't much options. 130 Defender has enough to use it's parts under diesel powered Chevy. Other would have been Toyota 70-series rear arms.

Why I'm doing this? I have front spring hangers and engine crossmember from blazer (which will have 3-link w/panhard), but that would have been basicly bolt-on operation. Yes, I want coils, but even more it's a matter of design and build, to create something different

I will tell you what brochures I need, but it's closer to safety inspection. I need lots of documents to make things easy.

I know what you mean by something different, my signature in other forums is "nothing ordinary"
When I was in the middle east I had the same situation you have, European parts were more available than american so I adapted what I had.
ALso wanted something different so I converted a Chevy van to 4wd using all custom made parts BY me.
Now I don't have time for such projects but have plenty of ideas

 

[4x4_76]

Now I don't have time for such projects but have plenty of ideas

I share your pain. I have head full of cool ideas, but the time, where is it? I've even thought about taking a week or two unpaid vacation from work to build my truck/s. But then again, that would be off from my budget, so no good.

But this 'Burban I have to get done, preferably before christmas. I'm going to sell my Dodge Ram after it clears safety inspection, so I need a roomy truck.

Couple of questions, is it possible to convert from liftgate to barn doors? Is there provision for door hinges on liftgate body?

And what is the max trailer weight, what you can tow with 4x4 diesel Suburban? Both, K10 and K20.

 

[imiceman44]

I share your pain. I have head full of cool ideas, but the time, where is it? I've even thought about taking a week or two unpaid vacation from work to build my truck/s. But then again, that would be off from my budget, so no good.

But this 'Burban I have to get done, preferably before christmas. I'm going to sell my Dodge Ram after it clears safety inspection, so I need a roomy truck.

Couple of questions, is it possible to convert from liftgate to barn doors? Is there provision for door hinges on liftgate body?

And what is the max trailer weight, what you can tow with 4x4 diesel Suburban? Both, K10 and K20.

It's funny I keep thinking the same thing, taking unpaid time off to do what I want.
Not now though I have a family to feed so fun will have to wait.
The tail gate style burbs up to a point had the provisions for the barn doors.
I don't know what the cuttoff year was but I do remember there was a thread about that so maybe a search in the last 2 years will show up some results.
As for towing numbers I will have to check for you, I have a K20 myself, and I am sure someone with a K10 burb will chime in with his numbers.

 

[imiceman44]

I share your pain. I have head full of cool ideas, but the time, where is it? I've even thought about taking a week or two unpaid vacation from work to build my truck/s. But then again, that would be off from my budget, so no good.

But this 'Burban I have to get done, preferably before christmas. I'm going to sell my Dodge Ram after it clears safety inspection, so I need a roomy truck.

Couple of questions, is it possible to convert from liftgate to barn doors? Is there provision for door hinges on liftgate body?

And what is the max trailer weight, what you can tow with 4x4 diesel Suburban? Both, K10 and K20.

Here you go:

http://coloradok5.com/forums/showthread.php?t=112369&highlight=barn+door+tail+gate

 

[4x4_76]

The tail gate style burbs up to a point had the provisions for the barn doors.
I don't know what the cuttoff year was but I do remember there was a thread about that so maybe a search in the last 2 years will show up some results.
As for towing numbers I will have to check for you, I have a K20 myself, and I am sure someone with a K10 burb will chime in with his numbers.

Thanks, I appreciate all your help

I have to do that barn door conv the hard way, pre -82 models had provision for doors. And mine is -82. But, that is not concern anytime soon, first I want it to be streetlegal.

I just received radius arms from -95 Defender, with new frame end rubber bushings, and polyurethane bushings on the axle end. Now I can actually start to do something visible

I decided to build separate coil towers and engine crossmember. Much easier that way. And if need comes, I can modifie towers just by unbolting them. Small problem is the steering shaft, because of it I have to make coil towers lower than I would like. But, we'll see what I come up with. I was also going to mount radius arms on top of the axle, but that would reduce already low spring height.

And for the material, I'm using 6 mm plate, and maybe on some places 8 mm. Stock Defender mounts are 3mm, but they are pressed to form. I can only bend and weld them, so I make them overkill, that way I won't need to make any calculations about the strenght of the mounts. My math isn't so good that I would able to do that, and I bet that inspector won't have a clue about those calculations anyway.

 

[4x4_76]

New plans... I decided to use D60 and shaved 14FF on 'Burban, which were originally going under the Blazer. But, since 'Burban is DD, and also some off-roading with 38.5 Boggers, I figured to go with bigger axels to keep it reliable. Also the t-case will be 205 w/NWF fixed output shaft. Why spend money on parts that you already have

This morning, while I was driving to work, I had an idea to use a 2wd front crossmember for coil towers and engine crossmember. Just lot of cutting and fitting, and I should have nice, sturdy parts.

I should get 'Burban to garage within couple of days. Then I get some pictures

 

[imiceman44]

New plans... I decided to use D60 and shaved 14FF on 'Burban, which were originally going under the Blazer. But, since 'Burban is DD, and also some off-roading with 38.5 Boggers, I figured to go with bigger axels to keep it reliable. Also the t-case will be 205 w/NWF fixed output shaft. Why spend money on parts that you already have

This morning, while I was driving to work, I had an idea to use a 2wd front crossmember for coil towers and engine crossmember. Just lot of cutting and fitting, and I should have nice, sturdy parts.

I should get 'Burban to garage within couple of days. Then I get some pictures

2wd cross member is definitely the way to start on a low budget coil setup.
That's how I was doing my van conversion before I left and some one took it to scrap yard

 

[4x4_76]

Made some test fitting with arms, and on the drivers side it fits perfectly. But on the passenger side, problem. I need to grind pumpkin to fit arm on the almost same location as were the leaf spring would be.

That pumpkin is huge, compared to D44. Hopefully I can make enough room for it under the crossmember.

 

[imiceman44]

Made some test fitting with arms, and on the drivers side it fits perfectly. But on the passenger side, problem. I need to grind pumpkin to fit arm on the almost same location as were the leaf spring would be.

That pumpkin is huge, compared to D44. Hopefully I can make enough room for it under the crossmember.

Well if you want it to articulate better, you want one side to be a pivot so you only need one end connected, modify the arm to bolt either on the bottom or the top and don't touch the axle

 

[4x4_76]

Well if you want it to articulate better, you want one side to be a pivot so you only need one end connected, modify the arm to bolt either on the bottom or the top and don't touch the axle

Unfortynately, modifying the arm is not possible. Well, for off-road only vehicle, yes, but for streetlegal truck, it needs to be as it is. I guess it will articulate just fine, I've seen couple of Range Rovers articulate quite nicely, and they had same kind of arms, all bolts mounted. Just some trick bushings were used.

Grinder, here I come

 

[imiceman44]

Unfortynately, modifying the arm is not possible. Well, for off-road only vehicle, yes, but for streetlegal truck, it needs to be as it is. I guess it will articulate just fine, I've seen couple of Range Rovers articulate quite nicely, and they had same kind of arms, all bolts mounted. Just some trick bushings were used.

Grinder, here I come

Then did you think about relocating the arms a little further out on the axle and relocating the buckets to fit?

 

[roadnotca]

Made some test fitting with arms, and on the drivers side it fits perfectly. But on the passenger side, problem. I need to grind pumpkin to fit arm on the almost same location as were the leaf spring would be.

Yeah but it would be awesome to react the pumpkin on the short side, and the tube on the long side. Just like the factory did with the springs. Perfecto.

 

[4x4_76]

Took the 2wd suspension apart yesterday. Hardest part was to pound off the u-bolts that hold lower a-arms Didn't took 'Burban to garage yet, I figured that crossmember build takes so much time that someone might need garage at the time. But, when I was looking at 2wd crossmember, I realized that I need to have truck in garage, otherwise it's quite hard to mount spring towers on right place. So now it's pretty difficult to move 'Burban without front suspension/tires

It's one possibility to move radius arms more out, but then I have clearence issues with 38,5 boggers I don't have rims done yet, and those 15 inchers won't fit w/o grinding the calibers. At least what I tried to fit them. Good thing is that center has not been welded to rim, so I can make propers backspacing. Maybe 3", we'll see. Or maybe I change boggers to 16 inchers, but then I would need to sell those half done beadlock wheels.

What if I mount those arms so that they are angled outboard on axle end, but at the frame they are on same widht as the spring perches on axle?

More deeper I go into this build-up, more problems rise up. But problems are made to be solved.

What comes to steering, I need to get Ford pitman arm, #1104 if I remember it correct, to make crossover steering. Eventually I'm using NWF hi-steer arms, but for now I make it like this: I take the tie rod from D60, turn it around so the steering damper hole is on the passenger side. Then I take tierod from D44, shorten it, and that goes from steering box to d60 tierod. I may need to move steering box forward, but hopefully it works on stock location.

 

[imiceman44]

Took the 2wd suspension apart yesterday. Hardest part was to pound off the u-bolts that hold lower a-arms Didn't took 'Burban to garage yet, I figured that crossmember build takes so much time that someone might need garage at the time. But, when I was looking at 2wd crossmember, I realized that I need to have truck in garage, otherwise it's quite hard to mount spring towers on right place. So now it's pretty difficult to move 'Burban without front suspension/tires

It's one possibility to move radius arms more out, but then I have clearence issues with 38,5 boggers I don't have rims done yet, and those 15 inchers won't fit w/o grinding the calibers. At least what I tried to fit them. Good thing is that center has not been welded to rim, so I can make propers backspacing. Maybe 3", we'll see. Or maybe I change boggers to 16 inchers, but then I would need to sell those half done beadlock wheels.

What if I mount those arms so that they are angled outboard on axle end, but at the frame they are on same widht as the spring perches on axle?

More deeper I go into this build-up, more problems rise up. But problems are made to be solved.

What comes to steering, I need to get Ford pitman arm, #1104 if I remember it correct, to make crossover steering. Eventually I'm using NWF hi-steer arms, but for now I make it like this: I take the tie rod from D60, turn it around so the steering damper hole is on the passenger side. Then I take tierod from D44, shorten it, and that goes from steering box to d60 tierod. I may need to move steering box forward, but hopefully it works on stock location.

Good luck on moving the burb the way it sits now, I have been there, it wasn't easy.
Mine had no front or rear axle and I had to move it from my RV access to my garage.
Let's just say it got interesting.

 

[4x4_76]

Good luck on moving the burb the way it sits now, I have been there, it wasn't easy.
Mine had no front or rear axle and I had to move it from my RV access to my garage.
Let's just say it got interesting.

I have couple of ideas how to move it. We'll see how it turns out.

I asked about the raduis arm mounting, and a few guys are running them like I described earlier, / \ axle end wider. They are supposed to flex better that way. That's the way I mount them, too.

If I can find one, I'm using panhard from Unimog. Seems to be long enough.

Just came to my mind, what is the front GAWR on 'Burban? I don't have registration card to mine because it has no plates.