SERVICE MANUAL Preload Pinion Bearing Pinion bearing preload is established by selecting the correct size spacer located between the two pinion thrust bearings  and  tightening  pinion  end  nut  to  the  specified torque (see "Torque Chart"). 1. Temporarily    install    companion    flange    on    end    of pinion shaft. IMPORTANT When preloading pinion bearings of forward rear axle, a spare companion flange and non-locking end nut in lieu  of  driven  gear  and  flange  nut  for temporary installation on pinion. Do  not  use  flange  type  lock  nut  during  bearing preload procedure. 2. Clamp   pinion   assembly   in   a   vise   so   as   to   hold companion flange. 3. Rotate    pinion    cage    while    tightening    end    nut    to specified  torque  (see  "Torque  Chart").    Rotation  of cage  is  important  so  as  to  seat  and  align  bearings, otherwise,  a  false   condition   of   bearing   load   could exist. Bearing rollers must be seated against face of bearing cone (Fig. 26). Fig. 26.  Pinion Bearing Roller Position 1 Correct 6 Cup 2 Cone 7 Clearance 3 Roller 8 Roller 4 Cup 9 Cone 5 Roller Against 10 Incorrect Face of Cone 4. Measure bearing preload by wrapping a strong cord or soft wire about the pinion Fig. 27.  Measuring Pinion Bearing Preload 1 Cord   or   Soft   Wire   Wrapped   Around   Pinion Cage 2 Spring Scale cage and attach end to spring scale (Fig. 27).  Read scale only while cage is rotating.  Compare this scale reading with the figure shown in "Specifications". When   preload   does   not   agree   with   Specifications bearing load may be increased by installing a thinner spacer   or   decreased   by   using   a   thicker   spacer. Determine spacer thickness using a micrometer (Fig. 28)  and  make  a  new  selection  accordingly.    Closer adjustment  may  be  obtained  by  working  spacer  to desired    thickness,    using    emery    cloth    on    a    flat surface. 5. Wash     spacer     clean     of     emery     cuttings     before installing on pinion. After   pinion   bearing   preload   is   established,   good practice would be to check bearing roller ends to see whether  they  are  in  contact  with  bearing  cone  face. Use   a   feeler   gauge   ribbon.      There   must   be   no clearance at ends of rollers (Fig. 26). Fig. 28.  Measuring Spacer Thickness CTS-4044 PRINTED IN UNITED STATES OF AMERICA Page 16