GM Service Manual Online
For 1990-2009 cars only

Engine Coolant Crossover Pipe Replacement L47

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 4.0 L.
  3. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 4.0L.

  4. Object Number: 490599  Size: SH
  5. Disconnect the brake booster vacuum tube from the water housing crossover.
  6. Disconnect the fuel regulator vacuum tube (1).
  7. Disconnect the secondary AIR solenoid vacuum tube (2).
  8. Remove the throttle body. Refer to Throttle Body Assembly Replacement in Engine Controls - 4.0 L.

  9. Object Number: 527521  Size: SH
  10. Disconnect the surge tank inlet hose from the fitting.
  11. Disconnect the fuel rail bracket retaining nut at the rear lift bracket.

  12. Object Number: 522707  Size: SH
  13. Remove the surge tank inlet fitting.
  14. Remove the rear lift bracket bolt.
  15. Remove the rear lift bracket.
  16. Remove the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 4.0 L.

  17. Object Number: 651462  Size: SH
  18. Disconnect the EGR inlet pipe nut (1) from the front exhaust manifold pipe.
  19. Important: The EGR valve inlet pipe incorporates a crush seal connection at the water crossover. The EGR valve inlet pipe must be replaced if disconnected from the water crossover.

  20. Remove the EGR inlet pipe bolt (2) and flange (3) from the water crossover.
  21. Remove the EGR inlet pipe and discard.
  22. Remove the EVAP emission canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls - 4.0L.

  23. Object Number: 522699  Size: SH
  24. Disconnect the electrical connector from the MAP sensor.
  25. Remove the MAP sensor.

  26. Object Number: 518338  Size: SH
  27. Position the J 38185  (2) to the clamp in order to remove the inlet radiator hose (1) from the water housing crossover.
  28. Remove the outlet radiator hose from the thermostat housing.
  29. Remove the water pump. Refer to Water Pump Replacement .

  30. Object Number: 500274  Size: SH
  31. Remove the two bolts (3) attaching the water pump belt tensioner (1) to the water crossover.
  32. Remove the water pump belt tensioner (1).

  33. Object Number: 550506  Size: SH
  34. Disconnect the cable harness clip at the water housing crossover and position aside.
  35. Disconnect the heater hose from the water housing crossover.
  36. Remove the water housing crossover from the engine.
  37. Clean and inspect the water crossover. Refer to Water Crossover Cleaning and Inspection in Engine Mechanical - 4.0 L Unit Repair.

Installation Procedure


    Object Number: 550504  Size: SH
  1. With all 8 crossover retaining bolts inserted, slide the upper and lower water housing crossover gaskets onto the bolts.
  2. Important: Care should be taken when installing the water housing bolts, so that the gaskets are in the correct position.

  3. Place the water housing crossover in position and hand start the bolts to hold the crossover in place.

  4. Object Number: 522930  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  5. Tighten the water housing crossover bolts.
  6. Tighten
    Tighten the water housing crossover bolts to 25 N·m (18 lb ft).

  7. Connect the heater hose to the water housing crossover.
  8. Connect the cable harness clip to the water housing crossover.

  9. Object Number: 500274  Size: SH
  10. Install the 2 bolts (3) attaching the water pump belt tensioner (1) to the water crossover.
  11. Tighten
    Tighten the water pump belt tensioner bolts (3) to 10 N·m (89 lb in).

  12. Install the water pump. Refer to Water Pump Replacement .
  13. Connect the outlet radiator hose to the thermostat housing.

  14. Object Number: 518338  Size: SH
  15. Position the J 38185  (2) to the clamp in order to connect the inlet radiator hose (1) to the water housing crossover.

  16. Object Number: 522699  Size: SH
  17. Install the MAP sensor.
  18. Connect the electrical connector to the MAP sensor.
  19. Install the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 4.0 L.

  20. Object Number: 651462  Size: SH

    Important: The EGR valve inlet pipe incorporates a crush seal connection at the water crossover. The EGR valve inlet pipe must be replaced if disconnected from the water crossover.

  21. Hand start the NEW EGR inlet pipe nut (1) to the front exhaust manifold pipe to prevent crossthreading.
  22. Tighten
    Tighten the EGR inlet pipe nut to 60 N·m (44 lb ft).

  23. Connect the EGR inlet pipe flange (3) to the water crossover.
  24. Install the EGR inlet pipe-to-water crossover flange bolt (2).
  25. Tighten
    Tighten the EGR inlet pipe bolt to 25 N·m (18 lb ft).

  26. Install the EVAP emission canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls - 4.0 L.

  27. Object Number: 522707  Size: SH
  28. Position the rear lift bracket to the water crossover.
  29. Install the rear lift bracket bolt.
  30. Tighten
    Tighten the rear lift bracket bolt to 24 N·m (18 lb ft).

  31. Install the surge tank inlet fitting.
  32. Tighten
    Tighten the surge tank inlet fitting to 47 N·m (35 lb ft).


    Object Number: 527521  Size: SH
  33. Connect the surge tank inlet hose to the fitting.
  34. Connect the fuel rail bracket retaining nut to the rear lift bracket.
  35. Tighten
    Tighten the fuel rail bracket retaining nut to 4 N·m (35 lb in).


    Object Number: 490599  Size: SH
  36. Connect the secondary AIR solenoid vacuum tube (2) to the housing crossover.
  37. Connect the fuel regulator vacuum tube (1).
  38. Connect the brake booster vacuum tube.
  39. Install the throttle body. Refer to Throttle Body Assembly Replacement in Engine Controls - 4.0 L.
  40. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 4.0 L.
  41. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 4.0 L.
  42. Fill the cooling system. Refer to Cooling System Draining and Filling .