Disassembly Procedure

Important:  Do not remove the needle bearing when removing the pitman shaft arm and its components.

1. Remove the pitman shaft seals and bearing. Refer to PITMAN SHAFT SEALS AND BEARING REPLACEMENT - OFF VEHICLE (670 GEAR)  or PITMAN SHAFT SEALS AND BEARING REPLACEMENT - OFF VEHICLE (700 GEAR)  .
2. Remove the housing end plug. Refer to STEERING GEAR HOUSING END PLUG REPLACEMENT - OFF VEHICLE  .
3. Turn the stub shaft counterclockwise until the rack piston (2) begins to come out of the steering gear housing (3).
4. Remove the rack piston plug (1).
5. Insert J 21552  into the bore of the rack piston (2).
6. Hold J 21552  tightly against the worm shaft while turning the stub shaft counterclockwise. Turning the stub shaft forces the rack piston (2) onto J 21552  . The rack piston balls remain in place.
   Fig 1: Removing Rack Piston Plug

   Courtesy of GENERAL MOTORS CORP.
7. Remove the following items as an assembly from the steering gear housing (9):
   • The rack piston (4)
   • The rack piston screws (8), clamp (7), ball guide (6) and balls (5)
   • J 21552 
8. Remove the spool valve assembly. Refer to STEERING GEAR VALVE REPLACEMENT - OFF VEHICLE (700 GEAR)  .
9. Remove the worm shaft (14).
10. Remove the thrust bearing (12) and the flat races (11, 13).

    Important:  When removing J 21552  , watch for falling piston balls (5) from inside the rack piston (4).

11. Remove J 21552  from the rack piston (4).
12. Remove the rack piston balls (5).
13. Remove the following items from the rack piston (4):
    1. The screws (8)
    2. The clamp (7)
    3. The ball guide (6)
    4. The remaining rack piston balls (5) in the ball guide (6)
14. Remove the teflon ring (2).
15. Remove the O-ring seal (3).
16. Clean all of the disassembled parts.
17. Inspect all of the disassembled parts for wear.
18. Replace the parts if necessary.
    Fig 2: Disassembling Steering Gear Housing

    Courtesy of GENERAL MOTORS CORP.