Sliding pillar suspension

In around 1904, the New Jersey inventor J. Walter Christie developed a better coil spring pillar suspension system, which may be the inspiration for that later used by Lancia on its Lambda from around 1922.

Sliding pillar suspension systems have also been used by several cyclecar manufacturers, the French maker Tracta, and in several prototype vehicles.

A drawback of the sliding pillar system is that the track changes with differential suspension movement, such as when one wheel rises over an obstacle (as can be seen in the diagram above).

The effective track is the hypotenuse AC or AD of the triangle ABC, where AB is the fixed pillar spacing.

Track variation is usually considered less important than changes in wheel camber, which is almost nonexistent in a sliding pillar system (see suspension geometry).