**OE replacement drag link end** Your Mercedes tie rod assembly consists of two parts; the inner tie rod and the outer tie rod end. The outer tie rod end is what attaches to the steering knuckle and it is responsible for pulling or pushing the steering knuckle. After tens of thousand of miles and exposure to the elements the rubber ball joint boot can deteriorate or tear causing the ball joint to fail. If you hear a clicking sound while turning the steering wheel it is likely due to a failed tie rod end ball joint.