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Home >> Infiniti >> 2011 >> QX56 AWD >> Repair and Diagnosis >> Suspension >> Suspension Control Systems >> HBMC >> Basic Inspection >> Check Shock Absorber For Malfunction >> Work Procedure
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Work Procedure

CAUTION:
  • Clean surrounding areas of oil injection jack using steam before starting operation, since there may be mud on it.
  • Clean suspension oil pump (special service tool: KV40107700) jack with steam before use.
  • Clean leak check plug (special service tool: KV40108400) jack with steam before use.
  • Check each shock absorber, one by one, in accordance with the following procedures.
  1. Lift up the vehicle.
  2. Remove protector of PPMU.
  3. Remove cap of oil injection jack.
  4. Install hose (A) of a suspension oil pump (SST: KV40107700) to oil injection jack.
    CAUTION:
    • Jack must be securely inserted until a click sound can be heard.
    • Pressure reducing valve (B) of the suspension oil pump must be closed.
    Fig 1: Identifying Suspension Oil Pump Hose And Pressure Reducing Valve
    G07045687Courtesy of NISSAN MOTOR CO., U.S.A.
  5. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations.
    CAUTION: Never loosen the needle valve more than required.
    Fig 2: Identifying Needle Valves Of PPMU
    G07045669Courtesy of NISSAN MOTOR CO., U.S.A.
  6. Set knob (A) of suspension oil pump to the direction as shown in the figure and check that reading of pressure gauge is 0 MPa.
  7. Tighten needle valves A, C, and E of PPMU.
    Fig 3: Identifying Knob Of Suspension Oil Pump
    G07045680Courtesy of NISSAN MOTOR CO., U.S.A.
  8. Disconnect upper side pipe or lower side pipe of each shock absorber.
    • For front shock absorber
    • Disconnect upper side pipe (B) of front shock absorber.
    Fig 4: Identifying Upper And Lower Side Pipes Of Front Shock Absorber
    G07045690Courtesy of NISSAN MOTOR CO., U.S.A.
    • For rear shock absorber
    • Disconnect lower side pipe (B) of rear shock absorber.
    Fig 5: Identifying Upper And Lower Side Pipes Of Rear Shock Absorber
    G07045691Courtesy of NISSAN MOTOR CO., U.S.A.
  9. Install a leak check plug (SST: KV40108400) (A) to the removed pipe and tighten the leak check plug to the specified torque.
    CAUTION:
    • O-ring must be free of scratches and damage.
    • Piping must be kept free of the intrusion of dust and dirt.

    Tightening torque : 5.0 N.m (0.51 kg-m, 44 in-lb) 

  10. Loosen lock nuts of needle valves B and D of PPMU and then tighten needle valves B and D.
  11. Loosening position of needle valve of PPMU varies according to shock absorber that is checked. Loosen needle valve of PPMU by approximately 2 rotations, as per the following table.
    CAUTION: Never loosen the needle valve more than required.
    Fig 6: Identifying Leak Check Plug (SST KV40108400)
    G07045692Courtesy of NISSAN MOTOR CO., U.S.A.
    SHOCK ABSORBER REFERENCE CHART

    Shock absorber Loosening position of needle valve
    Front LH C
    Rear LH C
    Front RH A
    Rear RH A
  12. Set knob (A) of suspension oil pump to the direction as shown in the figure.
  13. Apply pressure of up to 2.4 MPa.
  14. Go to step 15 when oil comes out from lower portion of shock absorber which pipe is removed from. Go to step  16 when oil does not come out.
  15. Replace shock absorber, since shock absorber has internal leakage. Refer to "REMOVAL AND INSTALLATION " (front), "REMOVAL AND INSTALLATION " (rear).
    Fig 7: Identifying Knob Of Suspension Oil Pump
    G07045677Courtesy of NISSAN MOTOR CO., U.S.A.
  16. Shock absorber that is checked is normal. Set knob (A) of suspension oil pump to the direction as shown in the figure and check that reading of pressure gauge is 0 MPa.
  17. Tighten the loosened needle valve of PPMU.
  18. Remove leak check plug from pipe. Install pipe to lower portion of shock absorber and tighten pipe to the specified torque.
    CAUTION:
    • O-ring must be free of scratches and damage.
    • Piping must be kept free of the intrusion of dust and dirt.

    Tightening torque : 5.0 N.m (0.51 kg-m, 44 in-lb) 

    Fig 8: Identifying Knob Of Suspension Oil Pump
    G07045680Courtesy of NISSAN MOTOR CO., U.S.A.
  19. Check other shock absorbers in accordance with procedures of steps 8 to 18.
  20. Tighten needle valves A, C, and E of PPMU to the specified torque, after completion of check.

    Tightening torque : 8.3 N.m (0.85 kg-m, 73 in-lb) 

  21. Loosen needle valves B and D of PPMU by approximately 2 rotations and then tighten lock nuts to the specified torque.
    CAUTION: Never loosen the needle valve more than required.

    Tightening torque : 20 N.m (2.0 kg-m, 15 ft-lb)