How To Install An Adjustable Rear Sway Bar

Slide the aluminum sway bar arms onto each end of the tube. If necessary, use a rubber mallet or a soft block of wood to drive the arms onto the bar. Don't hit the bar or tubes with a metal hammer because it could damage the splines, making installation impossible. To make sure both arms are indexed the same, lay the bar assembly on a level surface; it should lie flat and not wobble. Install the arm pinch bolts using the supplied fasteners with a washer under the head of each nut and bolt. Don't tighten; the arms will need to be adjusted later.

Bolt the installation plates on the outside of each sway bar arm as shown. Use the supplied hardware and lightly tighten the bolts. The installation plates keep the chassis brackets in the correct position and square on the car during installation. Install the plates so the remaining open hole is placed away from the sway bar tube, toward the end of the arms.

Next, bolt the chassis mounts to the inside of the installation plates. These brackets are specific to the driver and passenger side. Be sure the single vertical tab on the L-bracket is facing inboard and snug the hardware just tight enough so the bracket can still be pivoted with some effort.

On '99-and-newer Mustangs, Ford moved the rear brake line and added an additional exhaust hanger to each side. Both of these interfere with the sway bar chassis mounts and changes need to be made. There are two hangers-one for the tailpipe and one for the muffler. The tailpipe hanger will be eliminated. Altering the hangers won't cause any problems because you will revert to the '79-'98 hanger configuration, where there was only a single muffler hanger. We began our alteration by cutting the hanger that goes from the tailpipe to the rubber mount.

Remove the muffler hanger from the rubber mount, then unbolt the chassis hanger bracket from the car.

With the exhaust-hanger chassis bracket removed, cut off the portion that used to be connected to the tailpipe.

This is how the reinstalled muffler hanger looks. It reattaches to the muffler with the rubber mount and is identical to '79-'98 Mustangs. The tailpipe hanger is eliminated to make room for the sway bar chassis mount. As for the brake line, gently flex it out of the way just enough to allow clearance for the sway bar chassis mounts. Be careful not to kink the brake line; ensure it won't touch the tailpipe.

Measure the vertical distance from the rear axle centerline to the fender lip. Raise the front of the car on a level surface and support it with jackstands, then raise the rear by jacking under the differential. Place two jackstands under the torque boxes or the rear of the subframe and adjust the jackstands' height so the car's rocker panels are level to the ground. Lower the rear axle until the shocks top out, then take off the rear wheels, stock sway bar, and quad-shocks from the axle. Unbolt the rear shocks from the axle and be careful not to allow it to droop too far, which could damage the brake line. Remove the rear springs and place the jack under the center of the rear axle and raise it until the jack begins to lift the axle, which will unload the rear shocks. Unbolt the rear shocks from the axle and raise it so its centerline to the fender lip is the same as the previously taken measurement. Place the jackstands outboard on the axle under the control-arm mounts, which will mean that the car is supported at six points. Then, as shown here, rest the sway bar on another jackstand (or blocks of wood; we used a screw jack since the car was on a hoist) with the arms facing forward.

Next, mate the axle mounts to the axle; their exact position at this point isn't critical. As the mounts are mated, slide two U-bolts into place on each axle mount. Be careful not to pinch the brake lines. Thread the supplied Nylok nuts onto the U-bolts with washers under each nut. Leave the brackets slightly loose so they can pivot on the axle tubes. Never weld the axle mounts to the axle, which would cause the axle to warp.

Use floor jacks to raise the sway bar arms into position. Place the jacks in front of the installation plates rather than the rear to keep the sway bar from rotating upward behind the differential. Raise both arms evenly to firmly place and test-fit the chassis mounts against the bottom of the framerails. The final position of the two mounts is with each one completely touching the bottom of the rear subframe and inside the upper part of the bracket touching the horizontal portion of the upper control-arm mount. Use enough force with the jacks to hold the chassis mounts firmly against the bottom of the rear subframes and tighten the four axle-mount U-bolts. The U-bolts need to be tightened to hold the sway bar assembly in place for welding (or drilling for the bolt-in version). Tighten both ends of the U-bolts evenly.

Before the final tightening of the U-bolts, sand the areas to be welded until bare metal is exposed.

The final tightening of the U-bolts.