WARNING

When compressing any suspension system spring, be extremely careful to position the spring compressor properly.. If the spring were to pop out of the compressor, serious injuries or death could result.

With the coil spring and upper damper unit removed, you can now remove the shock cartridge. A new shock cartridge can be installed in the strut outer housing to restore the strut to perfect condition. Some manufacturers recommend that the strut shock absorber be rebuilt once the strut shock absorber is repaired or replaced. The strut can be reassembled and installed in reverse order of disassembly,.

NOTE

For exact procedures for the removal, repair, and installation of a strut assembly, refer to the manufacturer's service manual.

Spring Service

Springs require very little periodic service. Leaf spring service usually involves bushing replacement. Torsion bars require adjustment and coil springs require no periodic service.

Spring service requirements can be found in the service manual of the vehicle you are working on.

Spring fatigue (weakening) can occur after prolonged service. The fatigue lowers the height of the vehicle, allowing the body to settle toward the axles. This settling or sagging changes the position of the control arms, resulting in misalignment of the wheels. This condition also affects the ride and appearance of the vehicle.

To check spring condition or torsion bar adjustment, measure CURB HEIGHT (distance from a point on the vehicle to the ground). Place the vehicle on a level surface. Then measure from a service manual specified point on the frame, body. or suspension down to the shop floor. Compare the measurement to the specifications in the service manual. If the curb height is too low (measurement too small). replace the fatigued springs or adjust the torsion bar.

NOTE

For instructions on the removal and installation of springs. refer to the manu- facturer's service manual.

The vehicle should also be at CURB WEIGHT when checking spring condition and curb height. Curb weight is generally the total weight of the vehicle with a full tank of fuel and no passengers or cargo. Also, make sure nothing is in the passenger compartment that could possibly increase curb weight. Curb weight is given in pounds or kilograms.

REVIEW 2 QUESTIONS

Q1. What component of the suspension system prevents the control arm from swinging to the front or rear of the vehicle?

Q2. In the suspension system, what is the function of the stabilizer bar?

Q3. At what location on the control am is the ball joint attached?

Q4. What is the most common type of shock absorber used on modern vehicles?

Q5. On a vehicle that uses struts on the front, the struts replace what suspension component?

Q6. What term is used to describe the stiffness or tension of a spring?

Q7. The radial play of a ball joint can be checked by moving the wheel straight up and down. (T/F)

Q8. What tool is required to remove the coil spring form the strut?

STEERING SYSTEM

Learning Objective: Identify the major components of a steering system. Explain the operating principles of steering systems. Describe the differences between the linkage and rack and pinion type steering. Describe the operation of power steering. Describe service and repair procedures for manual and rack and pinion type steering mechanisms. Explain the service procedures for servicing power steering belts, hoses, and fluid.

The steering system allows the operator to guide the vehicle along the road and turn left or right as desired. The system includes the steering wheel, which the operator controls, the steering mechanism, which changes the rotary motion of the steering wheel into straight-line motion, and the steering linkage. Most systems were manual until a few years ago. Then power steering became popular. It is now installed in most vehicles manufactured today. The steering