Rear Leaf Center Pin and Clamps

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77 K20

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I'm going from a 3" block to a 4" shackle flip. I'm sure it will have some adjusting that needs to be done. I'll worry about it when I get around to replacing the 1.25-ton springs with a lift kit from ORD.

Is the plate for moving the axle forward and backward or to rotate the axle and set the pinion angle.


Sounds like a good plan- especially because it seems like sometimes the axle gets moved forward more on some trucks (mine's just a K20).

The plate is just for centering how the tire is placed in the wheel well.

The pinion angle is going to be tilted upwards automatically with the shackle flip- on a long bed with a 4" flip there is a chance it might be too much. Will know after you drive it.
 
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PrairieDrifter

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They offer pinion shims as well. They call that adjustment plate a zero rate block, and they have the top plate that sandwiches everything together
 
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LateOnTheBrakes

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Unless there is an exploded diagram or step-by-step guide with pictures I will have to wait to figure it out until I pull it apart. I've always been a visual learning. I've tried reading the instructions on the generalspringkc website but it's all gibberish to me until I get my hands on it.
 

LateOnTheBrakes

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Thanks. I was referring to the whole spring stack though. I'm not even clear how the center pin is located in the axle. But I have replacement clamps and bolts. If I find I need more parts it's no big deal. The truck sits on my family farm. I haven't got it on the road yet.
 

BKING33

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Pin just fits in a hole on the bracket on axle tube. I forgot to mention I did have add a shim on my cucv to correct pinion angle after installing the shackle flip kit
 

LateOnTheBrakes

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So I guess just to verify I am imagining this correctly... You have the axle with a hole in it and you have a stack that consists of the center pin going through a plate to plate butts up against the bottom of the springs and then you put the nut on top of the spring assembly. You stick the head of the center pin in the hole on the axle then you put shims between the axle and the plate or between the plate and the springs to get your angles and correct? I assume the location of the axle in the wheel well is a function of where you clamp the u-bolts. My shackle flip is only 4 in. I still have the stock 1.25 ton springs. I would not even do the shackle flip but I'm on a budget and the rear of the truck is lower than the front. The front has 3-in lift springs that are fairly new. I figure the shackle flip will give me the 1-in rise in the bed that looks right. That will be enough to get it on the road and see if the 1.25 ton springs are really as bad as everyone says they are.
 

PrairieDrifter

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The u bolts get clamped in the same position, because of the center pin. Shackle flips bring the rear of the springs down, thus moving the center pin on the leafs and whole axle forward. The plate simply aligns to the leafs center pin hole, the you choose the adjustment you need by those increments and the zero rate block has a center pin built into it and that slips into the hole on the leaf spring pad on the axle
 

Wallace6

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I just use Allen bolts, because the head is already round,no grinding or anything and grade 8 is common
 

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