toughest, most dirt-simple suspension designs ever, but that doesn't mean they can't be made better. For example, almost every Jeep CJ and YJ ever made has come with the front leaf-spring shackles mounted at the front of the Jeep (one version of the CJ-5 made for the military and referred to as the M38-A1 came with the front shackles on the rear of the front spring). What difference does having these shackles in the front or rear of the springs make, you ask? Plenty. But like manual versus automatic transmissions or black coffee versus cream and sugar, it is an argument that will never be decided definitively.
A leaf-spring suspension is made up of multiple curved steel blades, or leaves, bolted together so that they form a leaf pack. Each leaf in this pack is usually consecutively shorter than the leaf above it. Though the leaves are bolted together, they can go from curved to flat as the suspension flexes. If both ends of the leaf pack were firmly attached to the chassis, they would not flatten out and thus would not allow the suspension to flex at all. To deal with this flex, leaf springs have a shackle at one end that swivels to allow the leaf pack to grow longer. As the leaf spring grows longer, the axle moves toward the shackle end of the leaf pack.
This is where the debate arises. As your vehicle comes up to an obstacle, the front axle will want to move into the obstacle if the front shackle is at the front of the leaf pack. Proponents of the front shackle believe this is good because in theory it forces the tires to have more traction as the spring is being compressed and pushing the axle for-
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