[Russcharger]

For some time now, I've been very confused over several things regarding the springs, shackles, reversals, flips, dips, chips, rips, etc. Can someone explain in a very simple manner and easy enough to understand for someone who is confused on all terms, several things for me?

1) Shackle reveral - Is this where it is set up so that the fixed point (is that the hanger?) is up front and the moving point (the shackle?) is in rear? I read that this allows the spring to compress so that the axle moves up and backward, which is better for ride. Does this have any setbacks, problems, etc?

2) Shackle flip - Is this where only the shackle (which I'm assuming is the moving part of the system) is turned upside down or "flipped"? Now I've heard this gives 1" or 2" of lift. What's the reason for this? How does it pertain to lift, height, ride, articulation etc?

3) Axle wrap - I kinda have an understanding of this, but some more explanation would be greatly appreciated. What is it, how does it affect the ride etc? Also, I know the block contributes to this, so talk about suspensions with no block, and how the ride and etc will be.

4) Springs - Whats better for what, in other words, more leaves are better for ? less leaves for? thinner or thicker for? flatter or arched for?

Thanks to all for any explanations you can give. It seems sometimes that i get terms mixed up, so i get confused as people talk about what they are doing to their rigs. That's why I ask for a simple 3-grade sort of explanation. Again thanks all!!!

 

[Evildriver-3]

I went through alot of this in a similar post here not very long ago, but here we go again

1. is when you move the front pivot shackle to the rear of the spring, this isn't a Jeep site so we don't need to look at this any further.

2. is when you take your rear shackle that is now hung with the spring on top, you then take it and modify a few things hang the spring under the shackle and you gain some lift on 1 end about 3".

3. When you hit the gas the pinion wants to over run the ring gear and it makes the twist in the rear we call axle wrap, it is the pinion gear trying to free itself and making an upward force and it twists the entire rear, the idea is to use that force to aid in traction, it can be done and it works very well.

4. Leaf springs should be made to the vehicle there going in and if it's going to carry more weight is whether or not you add leafs to it.
For suspension travel you want a semi flat spring this way it will have equal movement in both directions, adding lenght to the shackle will help add some movement, so ideally when lifting the vehicle you would want a factory type arch and just move the spring mounts down

 

[RXT]

1) Shackle reveral - Is this where it is set up so that the fixed point (is that the hanger?) is up front and the moving point (the shackle?) is in rear? I read that this allows the spring to compress so that the axle moves up and backward, which is better for ride. Does this have any setbacks, problems, etc?

Yes the hanger is the fixed point at the front of the spring. The shackle is the movable component at the rear. The shackle allows the length of the spring to change as the spring flexes. Think of a bow and arrow. When you pull the bow string, the ends of the bow actually get closer as the string is drawn tighter. Because the axle is located at the center of the spring length, the axle only moves half the amount that the shackle moves. This movement is always towards the shackle end and in the direction of the spring deflection (either up or down)

2) Shackle flip - Is this where only the shackle (which I'm assuming is the moving part of the system) is turned upside down or "flipped"? Now I've heard this gives 1" or 2" of lift. What's the reason for this? How does it pertain to lift, height, ride, articulation etc?

There are two types of shackle mounting. If you look at the front suspension shackles, the shackles are mounted in compression. Anotherwords, the leaf spring is mounted below the frame mounted end of the shackle. The rear suspension shackle is mounted in tension, or the spring end is mounted above the frame mount end of the shackle. There are important differences for both. With the shackles mounted in tension, the shackles have a great deal of side to side stability because the weight of the truck on the shackle pulls it upright, however as the springs flexes, the shackles will swing in an arc, and as it does so, it must also lift the weight of the vehicle. By placing the shackles in compression, the springs actually become more flexable because they don't have to overcome the weight of the vehicle, however they have much less side to side stability. If you notice, aftermarket extended shackles have an "H" shape. The crossbar helps to stabilize the side to side loading of the shackle. But for really long shackles you'll need to add another stabilizer bar to the axle known as a track bar to limit side to side movement of the axle and the shackles.

3) Axle wrap - I kinda have an understanding of this, but some more explanation would be greatly appreciated. What is it, how does it affect the ride etc? Also, I know the block contributes to this, so talk about suspensions with no block, and how the ride and etc will be.

Axle wrap usually occurs under accelleration. You know simple laws of physics. For every action, there is an equal and opposite reaction. This happens in axles as well. As engine torque spins the ring gear to drive the vehicle foward, it applys an opposite reactive force which causes the entire axle housing to rotate in the opposite direction of the ring gear. Because the axle housing is bolted to the springs, they begin to deflect the springs into an "S" shape until the force on the springs build up to the point where they snap back. When they snap back, this happens violently and you are also likely to have a temporary loss of traction. Other than an irritating hopping, and loss of traction, axle wrap can break parts in the axle. You can eliminate axle wrap by adding a traction device such as ladder bars or links. These devices work by preventing the axle housing from rotating under torque and prevent the bunny hop effect.

4) Springs - Whats better for what, in other words, more leaves are better for ? less leaves for? thinner or thicker for? flatter or arched for?

There is no one answer fits all. Depending on how you use your truck, springs are tailored for each type of use.

Ed

 

[Gerhart]

4) generally:
- flat spring = supple / arched spring is not
- long spring = supple / short spring is not
- thin leaves = supple / thick leaves are not
- few leaves are supple / a lot of leaves are not

For each car, there's a specific rate of the springs.
Only things that can be (simply)changed are:
- arch
- leaf thickness

You can, for example, change the leaf thickness.
Let's say: original is six leaves of 5/16" each, making a package of 1-7/16".
This can be "generally" changed into eight leaves of 1/4".
This results in a more supple spring.
I say "generally", because there's more to a springrating than what I have mentioned above, but it's a good rule of thumb.