Correlation Study for Radial Lash in Sliding Bushings of a Steering System

Investigation of clunking noise in a steering system fitted into a test vehicle indicated radial lash in sliding bushings, which are press fitted into housings, as one of the possible causes for clunk. To study the behavior of sliding bush under the influence of assembly clamp loads, manufacturing tolerances and road loads, sliding bushings are modelled in more detail in the steering system finite element models. Further for correlating the bushing measurements from test vehicle to the finite element model, a radial lash output is derived which is not directly available in finite element software. Finally, the correlated model is used to assess the updated design and check for radial lash improvement.