Basic Concepts
This type of weight includes components supported by the springs.
sprung weight
The most common type of spring used on modern vehicles.
coil spring
This component dampens spring oscillations.
shock absorber
This suspension allows wheels to move independently.
independent suspension
This component connects control arms to the steering knuckle.
ball joint
This type of weight includes wheels, tires, and brakes not supported by springs.
unsprung weight
This spring type is commonly used on rear-wheel-drive trucks.
Leaf
A strut differs because it is also this type of component.
structural component (part of suspension structure)
This suspension connects both wheels with a solid beam.
solid axle (dependent suspension)
The steering knuckle is also called this.
spindle assembly
The main purpose of a suspension system is to absorb this.
road shocks / impacts
A torsion bar twists to provide this.
spring action (spring force)
Oil passing through valves creates this effect.
damping (hydraulic resistance)
A MacPherson strut system combines a shock and this.
coil spring
Control arms attach to the frame using these.
bushings
Suspension must keep tires in contact with this.
the road surface
Progressive springs change this as load increases.
spring rate (deflection rate)
Gas-charged shocks use this to reduce aeration.
nitrogen gas pressure
SLA stands for this type of control arm system.
Short-long Arm (double wishbone)
A Panhard rod controls this type of movement.
lateral (side-to-side) movement
This force occurs when a tire hits a bump and moves upward.
reaction force
This determines a coil spring’s load-carrying ability (3 factors).
metal diameter, coil diameter, and spacing of coils
Adjustable shocks change damping by controlling this inside the piston.
valve openings/orifice size
This suspension type uses two I-beams that pivot separately.
twin i-beam
This type of axle transfers power to the wheels.
Live axle (drive axle)