What fits into the mounting flange bolt holes to absorb vibration in the rack and pinion assembly?

In a rack and pinion assembly, rubber bushings are specifically designed to fit into the mounting flange bolt holes. Their primary function is to absorb vibrations and provide cushioning between the steering gear and the vehicle's chassis. This absorption of vibration is crucial because it enhances the comfort of the ride by minimizing road noise and harshness felt inside the vehicle while also improving the longevity of the steering components.

The use of rubber bushings helps to isolate the steering system from the vehicle body, mitigating the resonance that can occur during driving. This isolation is important for maintaining precise steering control and improving overall handling. In addition to vibration absorption, rubber bushings also assist in accommodating minor misalignments between the steering rack and the vehicle frame.

Other options like bearing cups, ball nuts, and locknuts serve different purposes in the steering system. Bearing cups are generally used to support rotation and reduce friction within the assembly, while ball nuts are involved in the mechanism that translates rotational motion into linear motion. Locknuts have a role in securing components in place but do not provide vibrational dampening. Thus, rubber bushings are the component specifically intended for vibration absorption in this context.