Understanding Tie Rods

Steering Component - Tie Rod

Tie rods are slender structural rods that are used as a tie and capable of carrying tensile loads only. A tie rod consists of an inner and an outer end. As the cross-section width is normally rather small, it would likely buckle under compression.

The tie rod transmits force from the steering center link or the rack gear to the steering knuckle. This will cause the wheel to turn. The outer tie rod end connects with an adjusting sleeve. This allows the length of the tie rod to be adjustable. This adjustment is used to set a vehicle’s alignment angle.

Measuring for Tie Rods or Drag Links
Measuring for Tie Rods

The working strength of the tie rod is the allowable working stress where the threads are cut. Rods are often made thicker at the ends. This then means that the tie rod does not become weaker when the threads are cut into it.

Tie rods are connected at the ends in various ways. But it is desirable that the strength of the connection is at least equal strength to that of the rod. The ends can be threaded and then passed through drilled holes or shackles. The shackle is a U-shaped piece of metal that is secured with a pin or bolt across the opening. It is then retained by nuts that are screwed on the ends.

Tie Rod Ends
Tie Rod Ends

If the ends are threaded right hand and left hand, the length between the points of loading may be altered. This then gives a second method for pre-stressing the rod. By turning it in the nuts the length will be changed.

A turnbuckle (a device that is used for adjusting the tension in tie rods) can accomplish the same purpose. Another way of making any end connections is to forge an eye or hook on the rod.

It is advisable that your vehicle’s steering and suspension systems are checked at least once a year. A complete wheel alignment is recommended as well. A worn tie rod can cause wandering, erratic steering and also major tire wear. If a tie rod is necessary then a wheel alignment will also be required because tie rod replacement will disturb the alignment setting.

How to Change Inner And Outer Tie Rod Ends