Suspension: Description and Operation

Fig. 1 Typical front suspension exploded view:

On this type front suspension, Fig. 1, each wheel is connected independently to the vehicle frame by upper and lower control arms, ball joints and a steering knuckle. The upper and lower control arms are designed and positioned to allow the steering knuckles to move in a prescribed three dimensional arc. Tie rods, connected to the steering knuckles, ensure the front wheels are held in the proper relationship to each other.
A ball joint is riveted to the outer end of the upper arm and is spring loaded to insure proper alignment of the ball in the socket.
The inner end of the lower control arm has pressed-in bushings. Two bolts, passing through the bushings, attach the arm to the frame. The lower ball joint is a press fit in the arm and attaches to the steering knuckle with a castellated nut that is retained with a cotter pin.
Rubber seals are provided on upper and lower shafts and at ball socket assemblies to exclude dirt and moisture from bearing surfaces. Grease fittings are provided at all bearing locations.