Hard Steering 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 this chapter. 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 troubles. 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. Q1. Q2. Q3. Q4. Q5. Q6. Q7. Q8. Q9. Q10. REVIEW  3  QUESTIONS What type of steering linkage design is used on most vehicles? 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 steering  gear? 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 systems? 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 steering? TIRES,  WHEELS,  AND  WHEEL BEARINGS 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 8-29