The drag link, sometimes also called the center link, connects the pitman arm to the steering arm. In some vehicles, it connects to the tie rod assembly. The drag link is the element that keeps both of your two front steering wheels in line. Connected at either end by a ball joint, the drag link is often bolted to the tie rod ends, which then control the angle that each front steering wheel makes - in relation to the direction the car is going. If you feel vibrations or wobbling when driving your car, one of the first things to check would be for looseness or play in the drag link.
How Steering Systems Work
Unlike a center link, the drag link does not connect to an idler arm, and has no inner tie rod ends attached to it. On some cars or trucks, the drag link swings from the front to the rear of the vehicle. In these cases, the drag link connects to the steering arm - located at the wheel. In some Jeeps, the drag link will swing from right to left on the vehicle, and will connect to the steering arm at the wheel. Drag links can be a solid one-piece design or an adjustable design. Many drag links have replaceable or rebuildable ends.