A lower suspension arm (control arm) is a triangular shaped assembly which is attached to the vehicle chassis using bushes. It works in conjunction with the upper suspension arm to hold the wheel in alignment. They both attach at the top point to a spindle via ball joints, which in turn is attached to the wheel. The result of these parts working in motion is that you get a smooth controlled ride with the wheels moving in synchronicity with the rest of the vehicle and move up and down freely.

When you hit a bump in the road, the lower suspension arm absorbs the pressure of the bump and ensures that the bottom of the tyre stays put.

lower suspension arms could break when driving over large potholes. Signs that a lower suspension arm is broken is indicated by a banging noise when driving over bumps or vibration of the steering wheel.

Other damage to the suspension arm could occur in the bushes that connect the lower suspension arm to the chassis. These can wear out through general wear and tear. You may notice uneven tyre wear in this case.