Chapter 112 - Suspension System Principles and Components

Question 1

Answer 1

Ladder Frame

Question 2

Answer 2

Perimeter Frame

Question 3

Answer 3

Stub-type Frame or Cradle

Question 4

Answer 4

Unibody Frame

Question 5

The area separating the engine compartment from the passenger compartment

Answer 5

Bulkhead

Question 6

Weight of the components that move up and down (springs, wheels, suspension links, struts, etc.)

Answer 6

Unsprung Weight

Question 7

Weight of vehicle that does not move up and down (engine, cabin, seats, frame, etc.)

Answer 7

Sprung Weight

Question 8

Suspension that allows movement of one wheel without affecting the opposite wheel, as in solid axles

Answer 8

Independent Suspension

Question 9

Part of the suspension that buffers between the suspension and frame to absorb vertical movement and transfers part of the vehicle weight to the suspension component (ex. lower control arm) it rests on

Answer 9

Spring

Question 10

Name 4 types of springs

Answer 10

Leaf Spring

Torsion Bar

Coil Spring

Air Spring

Question 11

The amount of force in pounds it takes to compress a spring 1 inch

Answer 11

Spring Rate (K)

Question 12

The 4 characteristics that affect strength of a coil spring

Answer 12

Coil Diameter

Number of Coils

Height of Spring

Diamater of Steel that Forms the Spring

Question 13

Name two examples to vary spring rate

Answer 13

Frequency of Coils in Spring (less to more dense)

Decreasing Coil Diamater (tapered)

Question 14

What is spring frequency and how is it affected?

Answer 14

The speed that a spring oscillates/bounces. Stiffer springs have a higher spring frequency than softer springs.

Question 15

The ratio of wheel travel to spring travel. For example, the coil spring mounted on a lower control arm compresses 1 inch per 2 inches that the wheel travels vertically.

Answer 15

Wheel Rate

Question 16

The specific area where a coil spring is mounted, usually lined with a hard rubber or plastic cushion called insulators

Answer 16

Spring Seat

Question 17

A scratch, nick, or pit caused by corrosion on a spring’s epoxy coating that can lead to spring failure

Answer 17

Stress Riser

Question 18

Springs constructed of one or more strips of long, narrow spring steel

Answer 18

Leaf Springs

Question 19

Part that holds the leaves of a leaf spring together

Answer 19

Center Bolt or Centering Pin

Question 20

How and to what are both ends of a leaf spring attached?

Answer 20

One is connected directly to the immovable frame, and the other is connected to a movable hanger called a shackle

Question 21

Why are shackles necessary?

Answer 21

It allows movement of the leaf spring, as it extends/straightens whena bump is hit

Question 22

A spring that is long, round, hardened-steel straight bar

Answer 22

Torsion Bar

Question 23

Describe how a torsion bar is mounted

Answer 23

One end is attached to a non-twisting adjustable anchor arm on the frame, and the other is attached to a control arm (generally LCA) that allows twisting

Question 24

Why are two suspension links (i.e. upper AND lower control arms) needed?

Answer 24

It prevents transverse (side-to-side/in-and-out) and longitudinal (forward-backward) movement of the wheels

Question 25

What is anti-squat?

Answer 25

Suspension design factor that prevents squatting of rear during acceleration, which can also break traction as axles rise when the rear squats

Question 26

What is anti-dive?

Answer 26

Suspension design factor that prevents the nose of vehicle from dipping during hard braking

Question 27

Part of suspension that:

Joins suspension to the wheel

Includes spindle where froont wheel bearings are attached

Provides pivot points between suspension and wheel

Answer 27

Steering Knuckle

Question 28

A steel shaft or pin found in I-beam suspensions that connects the steering knuckle

Answer 28

Kingpin

Question 29

Suspension link that connects the frame to the knuckle or wheel flange. Generally connected to knuckle via ball joint

Answer 29

Control Arm

Question 30

Allows front wheels to move up and down as well as side-to-side

Answer 30

Ball Joints

Question 31

Load-carrying Ball Joint

Answer 31

When coil spring is attached to top of upper control arm and upper ball joint is carrying weight of the vehicle

Question 32

Non-Load-Carrying (or Follower) Ball Joint

Answer 32

The ball joint not carrying weight of the vehicle, such as lower ball joint when coil spring is on upper control arm

Question 33

Name the two types of ball joint designs

Answer 33

Tension-Loaded (pull)

Compression-Loaded (push)

Question 34

Steel rods attached to lower control arm and frame that provide forward/backward support to control arms. Often found on vehicles using MacPherson or SLA suspensions

Question 35

Round, hardened steel bar attached to both lower control arms that operates by twisting the bar if one side of the vehicle moves up or down in relation to the opposite side. Used to prevent excessive body roll while cornering

Answer 35

Stabilizer Bar (also Anti-roll Bar, Sway-Bar, Anti-sway Bar)

Question 36

Dampens and controls the motion of vehicle’s springs, preventing continual bouncing after hitting bumps

Answer 36

Shock Absorbers

Question 37

Compression of Shock Absorber

Answer 37

Jounce

Question 38

Extension of Shock Absorber

Answer 38

Rebound

Question 39

Similar to a shock absorber, but also functions as a suspension link, often replacing the upper control arm

Answer 39

Strut