A rack and pinion is a pair of gears which convert rotational motion into linear motion. The circular pinion engages teeth on a flat bar - the rack. Rotational motion applied to the pinion will cause the rack to move to the side, up to the limit of its travel.
http://en.wikipedia.org/wiki/R...

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A rack and pinion is a pair of gears which convert rotational motion into linear motion. The circular pinion engages teeth on a flat bar - the rack. Rotational motion applied to the pinion will cause the rack to move to the side, up to the limit of its travel.
http://en.wikipedia.org/wiki/R...

sway bar (an·ti·roll bar)
safety feature for stabilizing vehicle : a cross-mounted metal bar incorporated in the suspension system of a motor vehicle, designed to prevent the vehicle from swinging dangerously or overturning
http://encarta.msn.com/diction...

bushing: application
In a car or other vehicle's suspension, rubber bushings are used to connect the various moving arms and pivot points to the chassis and other parts of the suspension. In order to minimise vibration, wear, and transmission of noise, they often incorporate flexible material such as rubber or polyurethane. These bushings often take the form of an annular cylinder of flexible material inside a metallic casing or outer tube. They might also feature an internal crush tube which protects the bushing from being crushed by the fixings which hold it onto a threaded spigot. Many different types of bushing designs exist.
http://en.wikipedia.org/wiki/B...

In my opinon: The rack and pinion replacement has nothing to do with the "bushing" and "sway bar"