Automotive Technology/Suspension and Steering

This page is written for those taking the ASE A4 test

Always mark the placement of any part before removal

Steering

Always disable the Air Bag system before any change to the steering column.

Steering Columns should be locked into place to preserve timing and prevent overextending the clock-spring.

Replace Bushings when they no longer hold the part in position. Replace Bearings when they have any visible play, or have a turning torque outside of specification.

Adjustments can affect front wheel toe

Diagnosis

Bump steer can be caused by

Loose idler arm
Loose rack mountings
Loose or damaged mounting

Steering wheel free play can be caused by

Worn couplings
worn u joint
Loose mounting

Steering problems are sometimes subframe alignment problems

Manual Steering Gears

Also known as worm gears

Noises, binding, looseness, hard steering point to bearing and lubrication problems.

Rack and Pinion Steering Gear

Other parts

Air bag Steering wheel Clock spring

Worm gear Idler arm Rack and pinion

Tie rods

Power Steering Units

Power steering uses hydraulic pressure to apply force to the worm gear or rack

Diagnosis

Weeping, or a slight fluid leak requires repair or replacement

inspect power steering fluid
Remove and replace power steering pump belt, tensioner, pulley
diagnose power steering pump problems
Remove and replace power steering pump
power steering pressure test
Remove and replace power steering hydraulics
Steering gear worm bearing preload and sector lash

Remove and replace steering gear seals and gaskets

Remove and replace rack and pinion unit
Remove and replace rack and pinion steering gear bellows/boots.
flush, fill, bleed power steering hydraulics
Diagnose, Remove and replace variable-assist steering systems

Rack and Pinion Steering: can provide assistance by applying pressure to one side

Steering Linkage

Inspect and adjust steering linkage geometry

Pitman arm

Pitman arm is only bent in collisions, and wears on other parts. These are pressed on, and are difficult to separate from the splines.

Center link

If bent, will affect front wheel toe

Idler arm

Remove and Replace tie rods
Remove and Replace steering linkage damper

Remove and Replace

Suspension

Front Suspension

Rear Suspension

Alignment

Frame

Frame

Springs

You should understand spring frequency, even if you never measure the frequency of the spring. Most spring are made of a chrome-vanadium alloy. Very tough stuff.