Spindle (automobile)

In automobiles, a wheel spindle is the part of a suspension system that carries the hub for the wheel and attaches to the upper and lower control arms.

Spindles are carried by steering knuckles or "uprights".^[1] Although the terms "steering knuckle" and "upright" are sometimes used interchangeably with "spindle", they all refer to different parts.^{[2][self-published source?]}