Your steering system is made of a linkage system that is attached
to the front wheels, the steering wheel and the steering gear.
Conventional steering system: The steering
gearbox contains a worm gear at the end of the steering column. The worm gear,
which resembles the threading on a screw, meshes with a sector gear connected to
the Pitman arm. Opposite the pitman arm is the idler arm, which parallels the
Pitman arm and duplicates its motions. Working together, they cause the center
link to move from side to side.
On both sides of the center link are tie rods,
which in turn are connected to ball-and-socket joints called tie rod ends. The
tie-rod ends are attached to the steering arms, which complete the system and
cause the wheels to turn.
To help the wheel pivot from left to right, and
to integrate the steering suspension with the vehicle's suspension, there are
upper and lower ball joints or king pins.
Rack and pinion steering system: Instead of a
worm gear, this system calls for a square-cut gear at the end of the steering
column, called a pinion gear. This gear meshes with a rack, which is simply a
length of steel with teeth cut into it. Turning the steering wheel makes the
rack move to the left or right.
The rack itself takes place of the center link
and idler arm. The tie-rods are connected to the opposite ends of the rack,
either with inner and outer tie-rod ends, or with outer tie-rod ends and a
ball-and-socket joint on the end of the rack itself. The lower ball joint helps
integrate rack and pinion steering with MacPherson strut arrangement.