2008+  Rear  Diff  Lockdown  System  

 2014-­‐05-­‐16  

Thank  you  for  purchasing  this  PERRIN  product  for  your  car!  Installation  of  this  product  should  only  be  performed  by  persons  experienced  with  installation  of  aftermarket  performance  parts  and  proper  operation  of  high  performance  vehicles.  If  vehicle  needs  to  be  raised  off  the  ground  for  installation,  the  installer  must  use  proper  jacks,  jack-­‐stands  and/or  a  professional  vehicle  hoist  for  

safety  of  the  installer  and  to  protect  property.  If  the  vehicle  is  lifted  improperly,  serious  injury  or  death  may  occur!    Please  read  through  all  instructions  before  performing  any  portion  of  installation.  If  you  have  any  questions,  please  contact  our  tech  department  prior  to  starting  installation.  We  can  be  reached  in  any  of  the  following  methods:  

 Email  Tech@PERRINperformance.com  

Instant  Chat  off  the  main  page  of  www.PERRINperformance.com  Or  simply  call  our  tech  team  at  503-­‐693-­‐1702  

 

Questions,  Comments  and  Suggestions  Contact:  Tech@PERRINperformance.com  Visit  Our  Website  for  Instant  Chat  Options  at  www.PERRINperformance.com  

Call  Our  Tech  Team  at  503-­‐693-­‐1702    

SUSPENSION  INSTALLATION  NOTE  Installation  of  this  product  is  a  modification  to  the  vehicle  suspension.  As  a  result,  the  vehicle  may  handle  differently  than  that  of  factory-­‐equipped  vehicles.  As  with  any  vehicle  extreme  care  must  be  used  to  prevent  loss  of  control  or  roll-­‐over  during  sharp  turns  or  abrupt  maneuvers.  Always  wear  seat  belts,  and  drive  safely,  recognizing  that  reduced  speeds  and  specialized  driving  techniques  may  be  required.  Failure  to  drive  this  vehicle  safely  may  result  in  serious  injury  or  death.  Do  not  drive  this  vehicle  unless  you  are  familiar  with  its  unique  handling  characteristics  and  are  confident  of  your  ability  to  maintain  control  under  all  driving  conditions.  Some  modifications  (and  combinations  of  modifications)  are  not  recommended  and  may  not  be  permitted  in  your  state  or  country.  Consult  your  owner’s  manual,  service  manual,  instructions  accompanying  this  product,  and  local  laws  before  undertaking  these  modifications.  You  are  responsible  for  the  

legality  and  safety  of  the  vehicle  you  modify  using  these  components.      

 SPECIAL  NOTES:  

• The  use  of  a  factory  service  manual  is  highly  recommended.  These  can  be  purchased  or  downloaded  online  at  http://techinfo.subaru.com.  • When  installing  Diff  lockout  bushings,  keep  in  mind  you  are  pressing  them  in  by  tighten  the  bolt  and  nut  securing  them  to  chassis.  This  needs  to  be  done  in  2  steps  do  to  limitation  on  

length  of  bolt  used  to  press  it  in.    

Parts  Included  with  the  PERRIN  Differential  Lock  Down:  • (2)  2008  WRX  Differential  Lockout  Bushings  • (4)  2008  Differential  Support  Lockdown  Bushings      • (2)  M12  Jam  Nuts  

 

Installing  Rear  Differential  Lockout  Bushings  1. Park  car  on  level  surface.  Using  a  suitable  commercial  hoist  or  jack,  raise  car  and  support  on  jack  stands.  2. We  highly  recommend  removing  rear  muffler  section  of  exhaust  to  add  extra  room  for  installing  bushings.    NOTE:  Some  swaybars  may  have  to  be  removed  in  order  to  gain  access  

to  bushings  and  bolts.  3. Locate  rear  differential  bushings  pressed  into  rear  subframe.    Remove  one  of  two  17mm  nuts  securing  differential  to  bushings  pressed  into  subframe.    NOTE:  If  stud  comes  out  with  

nut  this  is  ok.  4. Remove  stud  from  diff  cover  using  (2)  supplied  Jam  nuts  by  locking  them  together  and  unscrewing.    NOTE:  A  stud  removal  tool  will  also  work.    

 Shows  nut  removed,  and  jam  nuts  installed  ready  to  remove  stud  from  diff  cover.  

 5. Remove  jam  nuts  and  reinstall  OEM  nut  onto  stud  roughly  5  turns.  6. Lubricate  outside  of  PERRIN  Diff  lockout  with  antisieze  or  grease.  7. Because  you  are  using  the  stud  and  nut  to  press  bushing  into  subframe  the  tightening  of  nut  needs  to  be  done  done  in  2  stages.  8. Align  PERRIN  Differential  lockout  bushing  with  PERRIN  logo  facing  toward  back  of  car.    Lightly  tap  bushing  into  place  using  hammer.    This  is  not  necessary  but  helps  keep  bushing  in  

place  while  doing  next  step.  9. With  bushing  held  in  place,  thread  nut  and  stud  into  diff  cover  roughly  5  turns.    

 Shows  spacer  held  in  by  bolt  and  nut,  ready  for  first  step  in  pressing  spacer  in.  

 10. Continue  threading  nut/stud  into  diff  cover  until  differential  is  pulled  up  to  subframe.    You  will  feel  the  increase  in  tension  on  nut  when  this  happens.  Continue  threading  nut  until  

roughly  70-­‐ft-­‐lbs  of  torque  is  felt  on  nut.    NOTE:  Because  you  are  pressing  Lockout  bushing  into  subframe  using  bolts,  some  poping  may  occur.    When  step  is  complete,  PERRIN  Lockout  bushing  will  be  sticking  out  from  subframe  .125”  to  .25”.  

11. Remove  stud  and  nut  from  differential  cover.    Remove  nut  from  stud,  and  thread  nut  onto  stud  roughly  5  turns.    Reinstall  stud  into  diff  cover  as  far  as  you  can  by  hand.  12. Place  long  3/8”  extension  between  differential  and  subframe.    NOTE:  This  is  used  to  keep  OEM  differential  bushing  from  compressing  during  last  step.        

   

13. Tighten  nut/stud  into  diff  cover  while  holding  3/8”  extension  in  place.    Tighten  nut  to  50ft-­‐lbs.    When  step  is  completed,  PERRIN  lockout  bushing  will  be  flush  or  slightly  concave  with  subframe.  

14. Loosen  nut  enough  to  remove  3/8”  extension,  and  retighten  nut  to  50ft-­‐lbs.  15. Follow  these  same  steps  on  remaining  Differential  bushing.    

 Shows  spacer  completely  pressed  in,  ready  to  do  the  same  steps  on  remaining  side.  

   

Installing  differential  front  support  bushings  16. Using  high  quality  jack,  slightly  support  differential.  17. Remove  aluminum  differential  support  from  sub  frame  and  differential.    (2)  14mm  nuts  hold  support  to  differential,  and  (2)  17mm  through  bolts  and  nuts  hold  differential  support  to  

subframe.      18. Install  red  urethane  bushings  next  to  OEM  rubber  bushings,  around  center  mounting  points.    Make  sure  to  do  this  to  both  left  and  right  OEM  bushings.  NOTE:  2  bushings  install  on  

each  side  of  bushing.    

 Shows  diff  support  and  where  bushings  go.  

 19. Reinstall  differential  support  brace  into  subframe  making  sure  red  bushings  stay  in  place.  20. Install  nuts  securing  differential  support  to  differential  and  tighten  nuts  to  40-­‐ft-­‐lbs.  21. Install  bolts  through  subframe  and  differential  support.  Then  install  nuts  and  tighten  to  40  ft-­‐lbs.NOTE:    Wiggling  diff  around  and  jacking  up  diff  will  aid  in  getting  bolts  to  pass  

through  subframe  and  diff  support.  22.  Remove  jack  supporting  differential,  and  lower  car  from  jackstands.  23. Take  car  for  test  drive  and  listen  for  noises.  There  will  be  some  additional  drivetrain  noise,  this  is  completely  normal.  If  clunks  are  heard,  check  that  all  bolts  are  tight  and  take  for  

another  test  drive.    PERRIN  Performance  Highly  Recommends  These  Complimentary  Products:  

• PERRIN  PSRS  system  • PERRIN  front  and  rear  swaybars  22mm  and  25mm  

 FOR  QUESTIONS  &  COMMENTS  PLEASE  CONTACT  TECH@PERRINPERFORMANCE.COM  503-­‐693-­‐1702  Live  Chat  with  us  on  our  website