2wd to 4wd conversion

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bucket

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Thank I appreciate this. I would think the model/brand of spring would become important, as the rear eye would have to be on the small side to fit in there. I've heard of notching the frame for spring eye clearance. If using the stock forward spring mounts, I imagine is could be shimmed to hang the spring a little lower to compensate for lowering the rear of the spring. It would certainly get tight quick with an arched lift spring, as it not only moves back but up.
Sure, anything can be done with a flame wrench, big effin hammer and the right attitude I guess..
I would also be concerned about the clearance between the spring/axle mounts and the bottom of the frame. The 4x frame has a little more clearance in this spot too. But with a lift spring this would become a non-issue.

I think there might be a few other issues to deal with. For example (I think) the rear cab mounts on a crew cab 2x are different than 4x crew cab.

And take note this conversion you were so kind to show would only work with stock length springs. a long spring like a 52 would need the front mounts moved more forward. I believe the whole concept is really about hanging a longer spring for massive travel... which in reality is just more droop. Droop is where it's at in keeping tires on the ground!

Right, the spring eye size could be a big factor as well, but I think most of the good (softer) springs tend to have eyes on the smaller side. And yes, bigger lift springs with more arch are going to 'grow' much more, but they also tend to be on the shorter side when installed at ride height, which pulls the shackle forward and gives it more room for travel during compression. But a 1/2" longer shackle makes a big difference too, I neglected to take pictures of that.

Don't get me wrong, it's certainly a lot of work to convert. None of the correct holes are there, all the brackets are different and the 4x4 crossmember ain't gonna fit without at least minor modifications. It's a frustrating pain in the ass for a lot of people, but it is doable and can work.
 

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Right, the spring eye size could be a big factor as well, but I think most of the good (softer) springs tend to have eyes on the smaller side. And yes, bigger lift springs with more arch are going to 'grow' much more, but they also tend to be on the shorter side when installed at ride height, which pulls the shackle forward and gives it more room for travel during compression. But a 1/2" longer shackle makes a big difference too, I neglected to take pictures of that.

Don't get me wrong, it's certainly a lot of work to convert. None of the correct holes are there, all the brackets are different and the 4x4 crossmember ain't gonna fit without at least minor modifications. It's a frustrating pain in the ass for a lot of people, but it is doable and can work.


Yeah I know a few guys who did the B52 kit from DIY and each build was a different can of worms. Our trucks are Lego but also, millions made with about a million small variations... Millions of parts made by what... hundreds of dies? I bet if we could look at the profiles on a few dozen frames we would see differences here and there... depending on where they were stamped.

I think moving the front spring bracket forward could be a double gain.. moving the axle forward gives more tire clearance to the fender, increases attack angle up to an object, moves weight bias back. So perhaps putting that front mount in more or less one inch forward of where
it kinda should be.
And I would look at a small discreet notch in the frame for that crucial clearance. Fun.
 

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How hard is the reverse, 4wd to 2wd?
 

bucket

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How hard is the reverse, 4wd to 2wd?

Involved still, but a bit simpler. I know a guy that did that too, he's where I got some of my factory 4x4 parts.
 

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Okay, im seeing and reading about changing motor mounts and cross member, is this for clearance issues with stock springs? Im doing 4-6 of lift so I didn't think there be any clearance issues.
 

bucket

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Okay, im seeing and reading about changing motor mounts and cross member, is this for clearance issues with stock springs? Im doing 4-6 of lift so I didn't think there be any clearance issues.

The 2wd crossmember must go completely, it's in the way. I've seen where one guy left just the very top of the 2wd crossmember in place (enough to connect the frame rails and support the engine mounts) and cut away the rest of it. It looked a bit flimsy, but it seemed to work.
 

Jarrett Melvin

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Hi everybody, I've gone and went ahead with the conversion, on the 2wd 1 ton C&C, I've included some pictures, don't mind the hack job so far, but I've some what dry fitted the axle and springs I guess you could say just for curiosity, wonder what your guys thoughta are on clearance issues.

I've used a conversion kit from ORD and a 4 inch rough country lift.

To me, it looks as if everything will clear the old 2wd crossmember. Maybe even trim it down a bit.

If clears should I leave rather then hunt down a 4wd crossmember and mess with that. Just deal with how it looks underneath?


Just wondering what yours guys opinions are.

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bucket

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I see you have the factory frame reinforcement straps on the lower side of the rails. They seem to cause a lot of rust buildup and added strength may be negligible. Removing them will gain a little shackle clearance and you can run slightly longer (and thicker) shackles too. But really, with those rather stiff front springs, the shackles may not have much swing in them.
 

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I see you have the factory frame reinforcement straps on the lower side of the rails. They seem to cause a lot of rust buildup and added strength may be negligible. Removing them will gain a little shackle clearance and you can run slightly longer (and thicker) shackles too. But really, with those rather stiff front springs, the shackles may not have much swing in them.


That's true to, I've left as is for now until I got some feedback, but I'm mostly concerned about the crossmember clearance right now.

This is how everything sits right now, I'm not gunna be doing any offroad use really. Mostly gunna be a Sunday/weekend driver.

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bucket

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I'd be worried about the pumpkin hitting the crossmember for sure. You won't know for sure until you get weight on the springs and jack up the right front as high as you can.
 

Jarrett Melvin

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I'd be worried about the pumpkin hitting the crossmember for sure. You won't know for sure until you get weight on the springs and jack up the right front as high as you can.


I'm gunna go with it for now, see what happens, it's not to big a job to drop it back out if I have to
 

Craig 85

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Jarrett Melvin

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Okay so this is how it looks so far. Everything bolted in expect shocks and drag link. Did have clearance issues with the exhaust on drivers side and had to cut it out of the way but other then that everything went really smooth. Little tricky lining the holes for back side spring hangers. What do u guys think so far?

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I’d cut this spring pocket off and remove that upper bracket and weld a plate over the opening. That’ll clean up the wheel well and is completely ok structurally.

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I’m no expert on it, but all I know is the old saying how’s converting from 2wd to 4wd it won’t ever track down the road straight no matter what you do. I can’t recall who said that to me, but it was many years ago. I’d just get a true 4wd truck, save you troubles.
 

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