2wd to 4wd swap

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87silveradok20

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So I picked up a 1984 c30 with a 12 valve cummins for next to nothing last night. At the same time I picked up a Dana 60 front axle. So as you can imagine I want to put the axle under the truck. I was thinking of doing the b52 front spring hangers from DIY4X then the factory hangers in the back(drill holes and attach). Does this sound doable? Also what size spring pack will I need to hold the weight of the cummins? For steering I was going to use crossover steering. I have no idea what the best way for this set up is, so could someone point me in the right direction there. Pictures of the truck will come as soon as I go back to pick it up.. And those of you who have seen the k20 build thread and are wondering if it will be replaced. the answer is no, this will be the daily and the k20 will be the nice truck. (I know I need to update the build thread on the k20, im planning on doing that after i get it back from the body shop).
 

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I can post u some pics of my crossover steering on my d60 when I get home. What questions do u have I just did mine
 

bucket

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You are on the right track. Besides figuring out proper spring and shackle geometry, the engine crossmember may give you the biggest hassle. There are slight differences between C/K frame rails and I don't think anyone offers a crossmember specifically for converting a 2wd.
 

87silveradok20

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I can post u some pics of my crossover steering on my d60 when I get home. What questions do u have I just did mine

I have never done a crossover steering set up before, so just trying to inform myself before I try it. I've heard its better than factory steering, but if anyone would thing a factory steering set up would be better on this truck please let me know. And yes please post up some pictures of how you did yours.
 

87silveradok20

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You are on the right track. Besides figuring out proper spring and shackle geometry, the engine crossmember may give you the biggest hassle. There are slight differences between C/K frame rails and I don't think anyone offers a crossmember specifically for converting a 2wd.

Would the engine cross member have been changed for the cummins swap? And do you know what the differences in the frames is? With the B-52 spring swap, you are supposed to get around 4 inches of lift (or so ive heard), would this be enough to clear the cross member and what not? I can get some pictures later. I am planning on bringing it home tonight. If theres a better way to do what im trying to do please tell me because im open for suggestions.
 

87silveradok20

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Also I forgot to add originally I was planning on doing a divorced transfer case in the truck. does anyone have an pictures of how to do this in one of these trucks? I have a dodge tranny with OD in the truck.
 

bucket

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Would the engine cross member have been changed for the cummins swap? And do you know what the differences in the frames is? With the B-52 spring swap, you are supposed to get around 4 inches of lift (or so ive heard), would this be enough to clear the cross member and what not? I can get some pictures later. I am planning on bringing it home tonight. If theres a better way to do what im trying to do please tell me because im open for suggestions.

Your engine should be mounted to the stock crossmember with custom or adapter mounts. The 2wd crossmember ties the rails together, supports the engine and also is the foundation for the front suspension. The 4x4 crossmember basically just gives a place for the engine mounts to bolt up. It's not that strong and doesn't do much to tie the rails together. You would need mega high lift to leave the 2wd crossmember in place.

Were you planning on using 52" front springs? How high do you want the truck to be? What size tires do you want to run?
 

87silveradok20

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Your engine should be mounted to the stock crossmember with custom or adapter mounts. The 2wd crossmember ties the rails together, supports the engine and also is the foundation for the front suspension. The 4x4 crossmember basically just gives a place for the engine mounts to bolt up. It's not that strong and doesn't do much to tie the rails together. You would need mega high lift to leave the 2wd crossmember in place.

Were you planning on using 52" front springs? How high do you want the truck to be? What size tires do you want to run?

I was planning on using the 52" springs and I was just going to use the stock sized ones which give you about 4" of lift (at least thats what I have heard). How much lift will I need to use the 2wd cross member? But it will probably give me more because of going from 2wd to 4wd. I can check out the crossmember tomorrow and see how low it hangs.
 

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You will get more than 4" because your 2wd is lower than a stock 4x4. Probably 7 inches or so.

Run the heaviest 52's you can get your hands on. You might even have to add in a leaf or two. Just remove the thick overload leaf. It should still ride and flex very well. Add in bumpstops to keep the springs from going beyond flat.
 

87silveradok20

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You will get more than 4" because your 2wd is lower than a stock 4x4. Probably 7 inches or so.

Run the heaviest 52's you can get your hands on. You might even have to add in a leaf or two. Just remove the thick overload leaf. It should still ride and flex very well. Add in bumpstops to keep the springs from going beyond flat.

So do you think that I will get enough enough lift to clear the cross member? or will this just have to be a try it and see tyep of thing?
 

HotRodPC

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When figuring the crossmember, engine mounts, and springs, let's not forget that Cummins is a very heavy bitch. Everything you do up front needs to be on steroids.
 

oldchevy4x4

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There is no way you will clear a 2wd cross member with 4 inches (as in 4 above a normal 4x4). From looking into the same thing your best bet would be to ether use the ORD big block cross member or build something close to that


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87silveradok20

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How much lift do you guys think will be needed to clear the cross member?
 

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