What is the function of a control arm in a suspension system?

The function of a control arm in a suspension system is primarily to connect the wheel assembly to the vehicle's body, allowing for controlled movement while maintaining proper wheel alignment during suspension travel. This connection is crucial as it enables the wheels to move up and down when encountering bumps or other road irregularities, while also keeping the wheel positioned correctly relative to the vehicle chassis.

Control arms typically consist of a pivot point where they attach to the vehicle's body (often the frame) and a connection to the wheel hub. This setup allows for smooth vertical motion of the wheel while also absorbing impacts, thus contributing to the overall ride comfort and handling of the vehicle. Their design can vary, with some control arms featuring bushings or ball joints that allow for easier movement.

The support of the vehicle’s weight is a secondary function and involves various components, including springs and shock absorbers, working in tandem with the control arm. While fuel efficiency and the alignment of steering components are important aspects of a vehicle's performance, they are not direct functions of the control arm itself.