ward at the same time.
The rearward shackle team believes that moving the shackle to the rear of the leaf spring allows the axle to move backward upon encountering an obstacle, rock, ditch, and so on. They feel this is a better option because it takes the forward movement of the vehicle and allows for some relief from a jarring hit. They feel the rearward front shackle makes for a softer ride and a front suspension that's friendlier to high speeds.
A wrench can be easily thrown into this whole discussion: What if the leaf springs are flat, not curved? When a flat leaf spring has a front shackle, compression actually pushes the axle backward, and vice versa when it has a rear shackle. Whatever direction you choose, understanding why your shackles are the way they are is important.
IWe started with a ratty old '95 Jeep YJ that had broken leaf springs from its short but abusive life as a ranch tractor. The overall plan s to eventually put it on 35- or 37-inch tires, but for now we just wanted to replace the broken parts and get it a little higher in the air. We also wanted to showcase the process and theory of a shackle reversal. First we measured the center of the axle at ride height and at full droop. As you can see by the marks on the fender, the axle moves forward the more it compresses and rearward as it droops out. Removing all the front suspension parts was job number one. Old worn-out shocks were round-filed along with the broken leaf-spring packs and all bushings and shackles since we would be replacing them all. Be sure to keep the U-bolts, nuts, and plates if you didn't order new ones. We recommend always getting new U-bolts, but forgot to order them prior to this story.
2 The front shackle hanger and much of the frame on this old Jeep had been bit by the rust bug, but luckily it was mostly surface corrosion. We installed the new Mountain Off-Road Enterprise (M.O.R.E.) spring hangers so that they were aligned with the old shackle mount and the front bumper bolt holes. You will need to drill some holes in the frame and use the supplied sleeves. We also cut out the front, welded in nuts, and replaced them since they had long since rusted solid with the bumper bolts.
3 In the rear we use the Miller Spectrum 625 plasma cutter to make mincemeat of the original leaf-spring hanger. The hangers will be replaced with a shackle mount that runs through the framerail. Check out that new Prowler Series Hobart welding helmet with the mud-tire off-road theme. The autodarkening helmet can be set for darknesses, sensitivity, and delay, so it works for welding as well as plasma cutting and grinding.
4 With the front spring hangers installed, we installed our ARB/Old Man Emu Dakar 2%-inch YJ leaf springs and swung them up into place until they were 1 inch below the frame-rail. Then we installed the M.O.R.E. heavy-duty shackles and set them at 60 degrees to mark where we will be drilling the frame.
5 With the marks made, we used a 1%-inch hole saw to drill through the frame and then weld in the supplied M.O.R.E. frame sleeves. These sleeves were then fitted with the new Old Man Emu bushings to reassemble the suspension with a better ride and more vertical attitude.
6 With the new shackle reversal installed along with the Old Man Emu Nitro Charger shocks, we again measured the axle centerline movement and marked it on the fender (one benefit of an old project truck is that we can write notes right on the body). As expected, we found that the axle now moves forward as it droops and backward as it compresses. Shackle reversals often require a long-travel front driveshaft because the axle now has more travel than before.
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