Sample Review Questions:
1.
Counterman A says sealed “low friction” ball joints with polymer
bushings and polished ball studs are used in most late-model vehicles
to reduce friction and steering effort. Counterman B says if the “wear
indicator” on a ball joint is flush with the housing, it means the
joint is new. Who is right?
a. Counterman A only
b. Counterman B only
c. Both Counterman A and B
d. Neither one
2. Which of the following components should be replaced if a vehicle’s ride height is below specifications?
a. Tie rod ends
b. Ball joints
c. Control arm bushings
d. Springs
3. Which of the following components will cause rapid toe wear on the front tires if worn or loose?
a. Tie rod ends
b. Ball joints
c. Control arm bushings
d. Shocks absorbers or struts
4.
Counterman A says gas charged shocks contain high-pressure gas to help
support the vehicle’s weight. Counterman B says preassembled MacPherson
struts include new upper bearing plates and springs. Who is right?
a. Counterman A only
b. Counterman B only
c. Both Counterman A and B
d. Neither one
ANSWER KEY
1A, 2D, 3A, 4B
EXPLANATIONS:
1.
Ball joints are used to connect the control arms to the steering
knuckle. Suspensions with upper and lower control arms have four ball
joints (two upper and two lower). Strut suspensions usually have only
two lower ball joints, though some may also have an upper wishbone
control arm with one or more ball joints. Ball joints may also be used
in the rear suspension on some FWD cars.
A ball joint has a stud
that rides against a bearing. The ball joints in most late-model
passenger car and light truck have plastic (polymer) bearings that are
lubed for life and have no grease fitting. Older vehicles and some
trucks have ball joints with metal gusher bearings that do require
periodic greasing. Some ball joints have built-in wear indicators that
protrude from the housing when the joint is new. As the joint wears,
the indicator recedes into the housing. When the indicator is flush
with the housing, it’s time to replace the joint.
2. Tie rod
ends are part of the steering linkage, while ball joints and control
arm bushings are part of the suspension but have nothing to do with
ride height. It’s the springs that carry the weight and determine ride
height. Coil springs, leaf springs and torsion bars can all sag with
age, causing a loss of ride height that adversely affects wheel
alignment. Sagging coil and leaf springs should be replaced if ride
height is less than specifications. Torsion bars, however, can usually
be adjusted to restore ride height.
3. The tie rod ends connect
the steering linkage to arms on the steering knuckles or struts. If the
tie rod ends are worn, they can cause steering looseness and rapid toe
wear on the front tires. Worn ball joints or control arm bushings can
also cause tire wear, but it is typically shoulder wear (camber wear)
on the edge of the tire. Worn shocks or struts can produce cupped wear
on the tires.
4. The gas charge inside a shock absorber or strut
is there to prevent fluid foaming and aeration when the shock is
pumping up and down rapidly. Foaming reduces the resistance inside the
shock, and causes a loss of ride control called shock fade.
Preassembled struts have become a popular alternative to rebuilding old
struts because they are faster and easier to install. The preassembled
units come complete with new upper bearing plates and springs, items
which are often overlooked when replacing struts, and may cause
problems down the road unless they are in good condition.
Sections covered:
Automatic Transmission
Batteries
Brakes
Cooling System
Drivetrain
Emissions
Engine Mechanical Parts
Exhaust
Fuel System
HVAC
Gaskets
Ignition System
Manual Transmission
Suspension and Steering
Management