Panhard rod

A Panhard rod (also called Panhard bar or track bar) is a suspension link that provides lateral location of the axle. Originally invented by the Panhard automobile company of France in the early twentieth century, this device has been widely used ever since.

Overview

While the purpose of automobile suspension is to let the wheels move vertically with respect to the body, it is undesirable to allow them to move forward and backwards (longitudinally), or side to side (laterally). The Panhard rod restricts lateral movement. This is different from a traction bar, which controls axle wrap and suspension loading. The track bar or Panhard bar is a simple device, consisting of a rigid bar running sideways in the same plane as the axle, connecting one end of the axle to the car body or chassis on the opposite side of the vehicle. The bar attaches on either end with pivots that let it swivel upwards and downwards only, so that the axle can move in the vertical plane only. This does not effectively locate the axle longitudinally, therefore it is usually used in conjunction with trailing arms that stabilize the axle in the longitudinal direction. This arrangement is not usually used with a leaf spring suspension, where the springs themselves supply enough lateral rigidity, but only with coil spring suspensions.