If hard steering occurs, it is probably due to
excessively tight adjustments in the steering gearbox
or linkages. Hard steering can also be caused by low or
uneven tire pressure, abnormal friction in the steering
gearbox, in the linkage, or at the ball joints, or
improper wheel or frame alignment.
The failure of power steering in a vehicle causes
the steering system to revert to straight mechanical
operation, requiring much greater steering force to be
applied by the operator. When this happens, the power
steering gearbox and pump should be checked as
outlined in the manufacturer's service manual.
To check the steering system for excessive
friction, raise the front of the vehicle and turn the
steering wheel and check the steering system
components to locate the source of excessive friction.
Disconnect the pitman arm. If this action eliminates
the frictional drag, then the friction is in either the
linkage or at the steering knuckles. If the friction is
NOT eliminated when the pitman arm is disconnected,
then the steering gearbox is probably faulty.
If hard steering is not due to excessive friction in
the steering system, the most probable causes are
incorrect front end alignment, a misaligned frame, or
sagging springs. Excessive tire caster causes hard
steering. Wheel alignment will be described later in
Steering System Noises
Steering systems, when problems exist, can
produce abnormal noises (rattles, squeaks, and
squeals). Noises can be signs of worn components,
unlubricated bearingsor ball joints, loose components,
slipping belts, low power steering fluid, or other
Rattles in the steering linkage may develop if
linkage components become loose. Squeaks during
turns can develop due to lack of lubrication in thejoints
or bearings of the steering linkage. This condition can
also produce hard steering.
Some of the connections between the steering
linkage components are connected by ball sockets that
can be lubricated. Some ball sockets are permanently
lubricated on original assembly. If permanently
lubricated ball sockets develop squeaks or excessive
friction. they must be replaced.
Belt squeal is a loud screeching sound produced by
belt slippage. A slipping power steering belt will
usually show up when turning. Turning the steering
wheel to the full right or left will increase system
pressure and belt squeal. Belt squeal may be eliminated
by either adjusting or replacing the belt.
REVIEW 3 QUESTIONS
What type of steering linkage design is used on
The idler arm supports the pitman arm on the
passenger side of the vehicle. (T/F)
What steering linkage component is used to
fasten the center link to the steering knuckles?
In a manual steering system, what two factors
determine steering ratio?
What is the most common type of worm and nut
In a power steering system, what device supplies
hydraulic fluid under pressure to the other
components in the system?
What are the three major types of power steering
On a manual rack-and-pinion system, what
adjustment is required when there is excessive
play in the steering?
What is the most common steering problem?
What is the most probable cause(s) of hard
TIRES, WHEELS, AND WHEEL
Learning Objective: Identify and describe the parts of
a tire and the methods of tire construction. Explain tire
and wheel sizes. Describe tire ratings and the different
types of wheels.
Identify the parts of driving and
nondriving hubs and wheel-bearing assemblies.
Diagnose common tire, wheel, and wheel-bearing
problems. Describe tire inflation and rotation
procedures. Explain static and dynamic wheel balance.
Summarize the different methods for balancing tires
and wheels. Explain wheel-bearing service.
This section introduces the various tire designs
used on modern vehicles. It explains how tire and
wheels are constructed to give safe and dependable
service. This section also covers hub and