Replacing the stock rubber swaybar bushings with firmer urethane will improve your IRS-equipped car's handling by precisely locating the rear swaybar. Rubber bushings allow the swaybar to move up and down relative to the chassis because, rather than just allowing the swaybar to pivot, the rubber also compresses. When the swaybar compresses the bushings, instead of purely rotating, the swaybar is not providing the same roll resistance at all times, and the car's handling will not be consistent or predictable. Rubber bushings suffer significant deterioration after only a few short years. Urethane bushings will restore an older car's handling to better than new. These bushings fit the stock Ford IRS rear swaybar and its mounting brackets.