Chapter 70

Suspension Fundamentals

This type of suspension system is the “long short arm” suspension system.

Narrow lower a-arms require strut rods for support.

Note: Spring location

Which ball joint carries the load with this type of suspension system?

Diameter, material of the bar, and material of the stabilizer link bushings affect the amount of control. Control should be balanced front-to-rear. Stiffer than stock front stabilizers should be accompanied by rear stabilizers.

McPherson Strut Type

Worn suspension parts will also cause premature tire wear as well as make the vehicle unsafe to handle.

Lets look at some of the parts that need to be inspected when perform a wheel alignment service.

Control arm bushings are the “hinges” for the control arm. They provide up and down movement of the arm.

Ball joint are located on the other end of the control arms and provide a pivot point for the steering knuckle.

Worn ball joints will cause the wheel alignment to change when stress is acted upon it. Some ball joints require lubrication as part of lubrication maintenance.

Springs will wear out and sag over time. This will also change the alignment angles. The springs are responsible

for correct ride height.

The purpose of the shock absorber is to control vehicle spring, or jounce. Excessive spring movement means

excessive toe change and results in excessive tire wear.

Shocks generally should be replaced after five years of use.

Other parts that require inspection are;

1. Wheel bearings

2. Sway bar bushings

3. Strut rod bushings

4. Strike out bumpers