This is the MM adjustable...
This is the MM adjustable rear sway bar installed on Mike O'Donnell's '01 Bullitt. Great info pertaining to the bar's tuning and installation is detailed on MM's website and in its instructions. It's a top-quality piece of equipment made from high-grade components and works in any application-from mild street cars to the most radical purpose-built road racers.
It's no secret that Fox and SN-95 Mustangs can be made to corner as well as the best-handling exotic and sports cars in the world. One of the parts manufacturers that's adept at making that a reality is Maximum Motorsports.
Among the arsenal of suspension parts that MM offers for otherworldly cornering capabilities is an adjustable rear sway bar for '79-'04 Foxes and SN-95s. When ultimate handling is the goal, you need the ability to fine-tune the car's balance. A Mustang's stock rear sway bar certainly won't provide the tuning capabilities that the MM bar affords.
Offered in seven different sizes, the MM rear sway bar is more effective than the stock unit because of how it attaches to the axle and chassis. The stock sway bar mounts to the lower control arms and it acts through the control-arm bushings. MM's adjustable version mounts to the axle and acts directly on the chassis through end-links made of spherical rod-ends.
Adjustments in sway bar rate can be made by changing the position of the end links on the bar's arm. Moving the end links toward the bar effectively shortens the arm, therefore increasing the rate. Because of the mounting method and the shorter length of the bar, a smaller-diameter bar provides a wheel rate similar to a stock sway bar's.
To see an adjustable rear sway bar being installed, we stopped in at MM's San Luis Obispo, California, headquarters where the team was installing one in Mike O'Donnell's '01 Mustang GT Bullitt, which already had a full MM Maximum Grip Box. Installation, along with welding in two mounting brackets, was completed in about three hours.
Major pieces include the bar...
Major pieces include the bar tube itself, a pair of aluminum arms and axle mounts, driver- and passenger-side chassis mounts, rod ends, and related installation hardware. Bolt-in and weld-in versions are available, but we went with the weld-in version. Still, it's not a big deal because only the two chassis mounts are welded.
Begin sway bar assembly by...
Begin sway bar assembly by sliding both shaft collars onto the sway bar tube. Leave them loose in the center of the tube.
Slide one urethane bushing...
Slide one urethane bushing onto each end of the sway bar tube. The job will be cleaner if you don't grease the urethane until after the bar is completely mounted. As shown, install the U-brackets over the urethane bushings and onto the axle mounts.
Use the appropriate fasteners...
Use the appropriate fasteners and place one washer under the head of each nut and bolt. The outboard edge of the urethane should be about 1/2-1 inch away from the bar's splines. Tighten the bolts until snug; they don't need to be torqued to spec because they will be loosened later.
Slide the aluminum 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...
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...
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,...
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...
Remove the muffler hanger from the rubber mount, then unbolt the chassis hanger bracket from the car.
With the exhaust-hanger chassis...
With the exhaust-hanger chassis bracket removed, cut off the portion that used to be connected to the tailpipe.
This is how the reinstalled...
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...
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...
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...
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...
Before the final tightening of the U-bolts, sand the areas to be welded until bare metal is exposed.
The final tightening of the...
The final tightening of the U-bolts.
With our car on a hoist, we...
With our car on a hoist, we used screw jacks to hold the chassis mounts in place.
With the sway bar arms and...
With the sway bar arms and chassis mounts in place, gently move the shield and the fuel line on the passenger-side framerail before welding. Then weld the chassis brackets to the framerails and the brackets as illustrated in MM's instruction sheet.
The finished weld work with...
The finished weld work with the chassis mount installed on each side should look like this.
Once the chassis mounts are...
Once the chassis mounts are welded, remove the installation plates, which aren't used when the bar is installed. They're replaced with the spherical rod ends and hardware installed here. Assemble and install these per MM's instructions using the appropriate hardware. Reinstall the rear springs, shocks, and wheels. Here, the ends are attached to the forward holes in the chassis mount which is the full soft setting. Increase stiffness if necessary after testdriving the car. With the car's weight on its wheels (either on the ground, on ramps, or on a ramp hoist), check the alignment of the rod-end assemblies. To avoid binding, they should be vertical when viewed from the rear of the car. If adjustment is needed, it can be done by moving the bar's sideways location by resetting the shaft collars. The bar's overall width can also be adjusted by sliding the sway bar arms on the bar's splines. If their required width is beyond the range of adjustment allowed by the splines, use more washers on the rod-end mounting bolts.
Recheck alignment of the rod...
Recheck alignment of the rod ends. They should be vertical or nearly vertical. If adjustment is necessary, loosen and pivot the axle mounts slightly on the axle, being careful to keep the orientation of each axle mount the same with respect to the opposite side in order to not undo previous alignments. Complete the installation by securely tightening the U-bolts as shown.