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For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2003 🢒 Ascender - 4WD 🢒 Steering 🢒 Power Steering System 🢒 Power Steering Pump Replacement

Power Steering Pump Replacement 4.2L

Removal Procedure

    Object Number: 687439 Size: SH
  1. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 4.2L.
  2. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical - 4.2L.
  3. Install a drain pan under the vehicle.
  4. Disconnect the power steering pressure hose (1) from the power steering pump.
  5. Disconnect the power steering cooler hose (2) from the power steering pump.
  6. Disconnect the wiring harness from the wiring loom on the power steering pump.

    7. Object Number: 687444 Size: SH
  7. Remove the power steering pump mounting bolts.
  8. Remove the power steering pump.

    9. Object Number: 649303 Size: SH
  9. Remove the power steering pump pulley using J 25034-C .

Installation Procedure

    Object Number: 643361 Size: SH
  1. Install the power steering pump pulley using J 25033-C .

    2. Object Number: 245012 Size: SH
  2. Install the power steering pump pulley (1) flush against the end of the power steering pump shaft (2), with an allowable variance of 0.25 mm (0.010 in.)

    3. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 687444 Size: SH
  3. Install the power steering pump.
  4. Install the power steering pump mounting bolts.

    5. Tighten
    Tighten the power steering pump mounting bolts to 25 N·m (18 lb ft).


    Object Number: 687439 Size: SH
  5. Install the power steering cooler hose (2) to the power steering pump.
  6. Install the power steering pressure hose (1) to the power steering pump.

    7. Tighten
    Tighten the power steering pressure hose to 25 N·m (18 lb ft).

  7. Remove the drain pan from under the vehicle.
  8. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical - 4.2L.
  9. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 4.2L
  10. Bleed the power steering system. Refer to Power Steering System Bleeding .
  11. Inspect the power steering system for leaks and the hoses for clearance away from the frame and other components.

Power Steering Pump Replacement 5.3L

Removal Procedure
  1. Remove the drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical - 4.8L, 5.3L and 6.0L.
  2. Remove the PCM from PCM mounting bracket and move to the side. Refer to Powertrain Control Module Replacement in Engine Controls - 4.8L, 5.3L and 6.0L.

    3. Object Number: 841009 Size: SH
  3. Remove the power steering pressure hose (1) from power steering pump (2).
  4. Remove the power steering pump return hose (3) from power steering pump (2).

    5. Object Number: 841012 Size: SH
  5. Remove the power steering pump mounting bolts (3).
  6. Remove the power steering pump (1).
  7. Remove the power steering pump pulley. Refer to Power Steering Pump Pulley Replacement .
  8. If applicable, remove the power steering pump reservoir. Refer to Power Steering Fluid Reservoir Replacement - Off Vehicle .

Installation Procedure
  1. If applicable, install the power steering pump reservoir. Refer to Power Steering Fluid Reservoir Replacement - Off Vehicle .
  2. Install the power steering pump pulley. Refer to Power Steering Pump Pulley Replacement .

    3. Object Number: 841012 Size: SH
  3. Align the power steering pump (1) with mounting bolt holes on engine block (2).

    4. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the power steering pump mounting bolts (3).

    5. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 841009 Size: SH
  5. Attach the power steering pump return hose (3) to power steering pump (2).
  6. Attach the power steering pump pressure hose (1) to power steering pump (2).

    7. Tighten
    Tighten the fittings to 25 N·m (18 lb in).

  7. Install the PCM to PCM mounting bracket. Refer to Powertrain Control Module Replacement in Engine Controls - 4.8L, 5.3L and 6.0L.
  8. Install the drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical - 4.8L, 5.3L and 6.0L.
  9. Bleed the power steering system. Refer to Power Steering System Bleeding .