<P> The arrangements for adjusting the toe angle are not changed by introducing ball joints in the suspension, although it should be noted that the steering linkage itself must use 4 or more pivots, also usually ball joints, and in almost every vehicle ever made, some of these have been adjustable by having a threaded end and locknut, to enable the toe to be set precisely . </P> <P> This ability to fine - tune ball - jointed suspension allows manufacturers to make the automobile more stable and easier to steer, compared to the older kingpin style suspension . It may also be quieter and more comfortable, because lateral and fore and aft compliance in the suspension can be introduced in controlled amounts at the control arm inner pivots without compromising the integrity of the steering axis pivots, which are now ball joints instead of a king pin and trunnions . The smoother ride may also increase tire tread life, since the ball - joint suspension allows better control of suspension geometry and so can provide better tire - to - road contact . </P> <P> On modern vehicles, ball joints are the pivot between the wheels and the suspension of an automobile . They are today almost universally used in the front suspension, having replaced the kingpin / linkpin or kingpin / trunnion arrangement, but can also be found in the rear suspension of a few higher - performance autos . Ball joints play a critical role in the safe operation of an automobile's steering and suspension . </P> <P> Many currently manufactured automobiles worldwide use MacPherson strut suspension, which utilises one ball joint per side, between the lower end of the strut and the control arm, with the necessary small amount of articulation at the top of the strut being usually provided by an elastomeric bearing, within which is a ball bearing to allow free rotation about the steering axis . So, there are commonly only two ball joints in the suspension, however there will be at least four (track rod ends and rack ends) in the steering linkage . </P>

Where are ball joints located on a truck