STEERING & SUSPENSION
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 the 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 a MacPherson strut arrangement.