How Tie Rod Ends Work

Tie rod ends are the connecting link to the steering. There are always two tie rod ends; an inner and outer. The tie rod end itself is a ball held in a socket within the arm. This ball has a stud attached to it to allow it to be connected to either end of the steering mechanism. This ball and socket has a grease fitting with which to lubricate it. The ball is tight in the socket but has the ability to swivel. When tie rod ends become worn, they are loose in the socket and cause severe play in the steering input. If not replaced and they continue to wear, the ball will pop out of the socket and a total loss of steering will occur.

A simple hard bump can dislodge a severely worn tie rod end with the worst results imaginable. This is one part on the vehicle that can not be repaired. A worn tie rod end will cause tire wear and looseness in the steering. If this is suspected, jack up front of the vehicle to where the tires are just off the ground. Grasp the tire as wobble it left and right. If the tie rod end is bad it will be very easy to feel the slop in the tire or a lot of free movement to the left and right with no movement in the steering wheel.

On a conventional rear wheel drive vehicle with a steering gear box, the tie rod ends can be replaced separately. The tie rod ends are connected together by an adjustable threaded tube. Each tie rod threaded end is screwed into opposing ends of the tube. The inner tie rod is attached to a drag link and the other is attached to the spindle or the part the tire and wheel is mounted on. The threaded tube has two clamps and when loosened, is used to adjust the alignment.

On a front wheel drive or any vehicle with rack and pinion steering, there are two tie rod ends, however they differ in their attachment points. On a rack and pinion, the inner tie rod end resembles a drum stick with threads on the handle and a ball socket on the other end. The ball socket has threads to attach it to the rack. The outer tie rod end has a female threaded end that screws on to the shaft from the inner tie rod end and is secured in place by a lock-nut. The inner tie rod end is the tie rod that commonly wears out in most cars. It can be tested the same way as the conventional one tie rod end.