Knowledge

Definition

In automotive suspension, a steering knuckle or upright is that part that contains the wheel hub or spindle and attaches to the suspension and steering components. The terms spindle and hub are sometimes used interchangeably with steering knuckle but refer to different parts.

The wheel and tire assembly attach to the hub or spindle of the knuckle where the tire/wheel rotates while being held in a stable plane of motion by the knuckle/suspension assembly.

In the attached photograph of a double-wishbone suspension, the knuckle is shown attached to the upper control arm at the top and the lower control arm at the bottom. The wheel assembly is shown attached to the knuckle at its center point. Note the arm of the knuckle that sticks out, to which the steering mechanism attaches to turn the knuckle and wheel assembly.

Classification

Steering knuckles come in all shapes and sizes. Their designs differ to fit all sorts of applications and suspension types. However, they can be divided into two main types. One comes with a hub and the other comes with a spindle.

Why Steering Chuckle Is Important?

The steering knuckle is the pivot point of the steering system, which allows the wheels to turn. On cars with conventional suspension systems, the steering knuckle's spindle locates and supports the inner and outer wheel bearings.