Express, Savana, G1500, G2500, G3500, 1998-2005

Cylinder Head

Print

Removal & Installation



4.3L Engine
  1. Drain the coolant.
  2.  
  3. Remove or disconnect the following:

    Negative battery cable
     
    Engine cover, if equipped
     
    Fan shroud
     
    Intake manifold
     
    Exhaust manifold
     
    Air pipe at the rear of the right cylinder head, if applicable
     
    Alternator mounting bolt at the right cylinder head
     
    Alternator, if necessary
     
    Power steering pump and brackets from the left cylinder head and lay aside
     
    Air conditioner compressor, and lay aside
     
    Spark plug wires at their brackets
     
    Ground strap from the right side and the coolant sensor wire from the left head
     
    Cylinder cover
     
    Spark plugs
     
    Pushrods. Identify the pushrods so that they can be installed in their original positions.
     
    Cylinder head bolts in the reverse order of the tightening sequence
     
    Cylinder head and gasket
     

  4.  

To install:

  1. Clean all gasket mating surfaces.
  2.  
  3. Install or connect the following:
    NOTE
    Be sure the gasket has the word HEAD up.


    NOTE
    Coat a steel gasket on both sides with sealer. If a composition gasket is used, do not use sealer.



    New gasket
     



    Cylinder head
     

  4.  
  5. Clean the cylinder head bolts, apply sealer to the threads, and hand-tighten.
  6.  
  7. Install the cylinder head bolts in sequence to 22 ft. lbs. (30 Nm) The bolts must, then be tightened again in sequence in the following order:
    1. Step 1: Short length bolt: (11, 7, 3, 2, 6, 10) 55 degrees.
    2.  
    3. Step 2: Medium length bolt: (12, 13) 65 degrees.
    4.  
    5. Step 3: Long length bolts: (1, 4, 8, 5, 9) 75 degrees.

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-4.3L engine

    6.  

  8.  
  9. Install or connect the following

    Pushrods (adjust the rocker arms, if necessary)
     
    Spark plugs
     
    Rocker arm cover
     
    Air conditioner compressor
     
    Power steering pump and brackets
     
    Alternator or the alternator mounting bolt at the cylinder head
     
    Air pipe at the rear of the head if removed
     
    Exhaust manifold
     
    Intake manifold
     
    Engine cover, if removed
     

  10.  
  11. Refill the engine with coolant.
  12.  
  13. Connect the negative battery cable.
  14.  

Left Side
  1. Remove or disconnect the following:
    NOTE
    Clean all dirt, debris, and coolant from the engine block cylinder head bolt holes. Failure to remove all foreign material may result in damaged threads, improperly tightened fasteners or damage to components.



    Battery negative cable
     
    Coolant
     
    Accessory drive belt
     
    Cooling fan assembly
     
    Power steering pump mounting bracket
     
    Power steering pump mounting bracket stud from the cylinder head
     
    Lower intake manifold
     
    Exhaust manifold
     
    Spark plug wire harness and the spark plug wire support
     
    Valve pushrods
     
    Ground strap and ground wire bolt from the rear of the cylinder head
     
    Engine Coolant Temperature (ECT) sensor (if applicable)
     
    ECT gauge sensor (if applicable)
     
    Spark plugs
     
    Spark plug wire support
     
    Cylinder head bolts
     
    Cylinder head and the gasket
     

  2.  
  3. Clean the cylinder head bolts and the engine block bolt holes.
  4.  

To install:

  1. Inspect the dowel pins (cylinder head locator) for proper installation.
    NOTE
    Do not use any type sealer on the cylinder head gasket (unless specified).

  2.  
  3. Install or connect the following:

    NEW cylinder head gasket in position over the dowel pins (cylinder head locator)
     
    Cylinder head onto the engine block. Guide the cylinder head carefully into place over the dowel pins and the cylinder head gasket.
     
    Sealant GM P/N 12346004, or equivalent, to the threads of the cylinder head bolts
     
    Cylinder head bolts finger-tight

    Click image to see an enlarged view

    Fig. Dowel pin installation-4.3L engines

     

  4.  
  5. Tighten the cylinder head bolts in sequence:
    1. First pass: 22 ft. lbs. (30 Nm).
    2.  
    3. Second pass: Long bolts (1, 4, 5, 8, and 9)-+ 75 degrees.
    4.  
    5. Second pass: Medium bolts (12 and 13)-+ 65 degrees.
    6.  
    7. Second pass: Short bolts (2, 3, 6, 7, 10, and 11)-+ 55 degrees.
    8.  

  6.  
  7. Install or connect the following:

    Spark plug wire support and bolts. Tighten to 106 inch lbs. (12 Nm).
     
    Spark plugs. Tighten to 11 ft. lbs. (15 Nm), if USED; 22 ft. lbs. (30 Nm), if NEW.
     

  8.  
  9. If reusing the ECT gauge sensor (if applicable), apply sealant GM P/N 12346004 or equivalent to the threads of the ECT gauge sensor. Install the ECT gauge sensor (if applicable). Tighten the sensor to 15 ft. lbs. (20 Nm).
  10.  
  11. Install or connect the following:

    Ground strap and the ground wire bolt. Tighten the bolt to 12 ft. lbs. (16 Nm).
     
    Valve pushrods
     
    Lower intake manifold
     
    Exhaust manifold
     
    Stud for the power steering pump mounting bracket to the cylinder head. Tighten the power steering pump mounting bracket stud to 15 ft. lbs. (20 Nm).
     
    Power steering pump mounting bracket
     
    Engine cooling fan assembly
     
    Coolant
     
    Battery negative cable
     

  12.  

Right Side
  1. Remove or disconnect the following:

    Battery negative cable
     
    Coolant
     
    Engine cooling fan assembly
     
    Alternator mounting bracket
     
    Alternator mounting bracket stud from the cylinder head
     
    Lower intake manifold
     
    Exhaust manifold
     
    Spark plug wire harness and spark plug wire support
     
    Valve pushrods
     
    Cylinder head and the gasket
     

  2.  
  3. Clean the engine block and the cylinder head sealing surfaces.
  4.  

To install:

  1. Inspect the dowel pins (cylinder head locator) for proper installation.
    NOTE
    Do not use any type sealer on the cylinder head gasket (unless specified).

  2.  
  3. Install or connect the following:

    NEW cylinder head gasket in position over the dowel pins (cylinder head locator)
     
    Cylinder head onto the engine block. Guide the cylinder head carefully into place over the dowel pins and the cylinder head gasket.
     
    Sealant GM P/N 12346004 or equivalent to the threads of the cylinder head bolts
     
    Cylinder head bolts finger-tight
     

  4.  
  5. Tighten the cylinder head bolts in sequence:
    1. First pass: 22 ft. lbs. (30 Nm).
    2.  
    3. Second pass: Long bolts (1, 4, 5, 8, and 9)-+ 75 degrees.
    4.  
    5. Second pass: Medium bolts (12 and 13)-+ 65 degrees.
    6.  
    7. Second pass: Short bolts (2, 3, 6, 7, 10, and 11)-+ 55 degrees.
    8.  

  6.  
  7. Install or connect the following:
    NOTE
    The front spark plug wire support bolt is used to fasten the oil level indicator tube, and will be installed within the oil level indicator tube installation procedure.



    Spark plug wire support and bolts. Tighten only the rear support bolt to 106 inch lbs. (12 Nm).
     



    Front spark plug wire support bolt
     
    Spark plugs. Tighten to 11 ft. lbs. (15 Nm), if USED; 22 ft. lbs. (30 Nm), if NEW.
     
    Valve pushrods
     
    Lower intake manifold
     
    Spark plug wire harness and wire support. Tighten to 106 inch lbs. (12 Nm).
     
    Exhaust manifold
     
    Stud for the alternator mounting bracket. Tighten the alternator mounting bracket stud to 15 ft. lbs. (20 Nm).
     
    Alternator mounting bracket
     
    Engine cooling fan assembly
     
    Coolant
     
    Battery negative cable
     

  8.  

4.8L, 5.3L & 6.0L Engines
Left Side

CAUTION
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures.

  1. Remove or disconnect the following:
    NOTE
    The M11 cylinder head bolts are NOT reusable. Install NEW M11 cylinder head bolts during assembly.



    Negative battery cable
     
    Intake manifold
     
    Push rods
     
    Exhaust manifold(s)
     
    Alternator
     
    Alternator mounting bracket-to-cylinder head bolts
     
    Bolt behind the power steering pump
     
    Alternator mounting bracket and set it aside
     
    Oil level indicator tube-to-cylinder head bolt
     
    Oil level indicator tube
     
    Cylinder head from the engine
     
    Spark plugs
     

  2.  
  3. Remove the cylinder head bolts.
    NOTE
    After removal, place the cylinder head on two wood blocks to prevent damage.

  4.  
  5. Remove the gasket. Discard the gasket. Discard the M11 cylinder head bolts.
  6.  

To install:


NOTE
Do not use any type sealant on the cylinder head gasket (unless specified). The cylinder head gaskets must be installed in the proper direction and position.

  1. Clean the engine block cylinder head bolt holes (if required). Thread repair tool J 42385-107 may be used to clean the threads of old threadlocking material.
  2.  
  3. Spray cleaner GM P/N 12346139, P/N 12377981, or equivalent into the hole.
  4.  
  5. Clean the cylinder head bolt holes with compressed air.
  6.  
  7. Check the cylinder head locating pins for proper installation.
    NOTE
    When properly installed, the tab on the left cylinder head gasket will be located left of center or closer to the front of the engine.

  8.  
  9. Install or connect the following:

    NEW left cylinder head gasket onto the locating pins
     
    Cylinder head onto the locating pins and the gasket
     
    NEW M11 cylinder head bolts.
     

  10.  
  11. Apply a 0.20 in. (5mm) band of threadlock GM P/N 12345382 or equivalent to the threads of the M8 cylinder head bolts.
    NOTE
    First design engine blocks have different drill and tap depths using both medium length 3.94 inch (100mm) and long 6.1 inch (155mm) M11 cylinder head bolts. Second design engine blocks use only the medium length 3.94 inch (100mm) bolt with a common drill and tap depth.



    M8 cylinder head bolts
     



    M8 cylinder head bolts.
     

  12.  
  13. Tighten the first design cylinder head bolts as follows:
    1. M11 bolts 1st pass: in sequence to 22 ft. lbs. (30 Nm).
    2.  
    3. M11 bolts 2nd pass: in sequence + 90 degrees.
    4.  
    5. M11 bolts (1,2,3,4,5,6,7,8): + 90 degrees.
    6.  
    7. M11 bolts (9 and 10): + 50 degrees.
    8.  
    9. M8 cylinder head bolts (11,12,13,14,15) to 22 ft. lbs. (30 Nm). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.
    10.  

  14.  
  15. Tighten the second design cylinder head bolts as follows:
    1. M11 bolts (1-10) 1st pass: in sequence to 22 ft. lbs. (30 Nm).
    2.  
    3. M11 bolts (1-10) 2nd pass: in sequence + 90 degrees.
    4.  
    5. M11 bolts (1-10): + 70 degrees.
    6.  
    7. M8 cylinder head bolts (11,12,13,14,15) to 22 ft. lbs. (30 Nm). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.
      NOTE
      The cylinder head gasket displacement can be verified by markings visible on the top side of the left gasket locating tab. Some 4.8/5.3L head gaskets may have 53 stamped onto the locating tab. Some 6.0L head gaskets may have 60 stamped onto the locating tab.

    8.  

  16.  
  17. Install or connect the following:

    Alternator mounting bracket. Tighten the four bolts to 37 ft. lbs. (50 Nm).
     
    Bolt at the rear of the power steering pump and tighten to 37 ft. lbs. (50 Nm).
     
    Exhaust manifold(s)
     
    Pushrods
     
    Intake manifold
     
    Negative battery cable
     

  18.  


CAUTION
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures.

  1. Remove or disconnect the following:
    NOTE
    The M11 cylinder head bolts are NOT reusable. Install NEW M11 cylinder head bolts during assembly.



    Negative battery cable
     
    Intake manifold
     
    Push rods
     
    Exhaust manifold(s)
     
    Alternator
     
    Alternator mounting bracket-to-cylinder head bolts
     
    Bolt behind the power steering pump
     
    Alternator mounting bracket and set it aside
     
    Oil level indicator tube-to-cylinder head bolt
     
    Oil level indicator tube
     
    Cylinder head from the engine
     
    Spark plugs
     

  2.  
  3. Remove the cylinder head bolts.
    NOTE
    After removal, place the cylinder head on two wood blocks to prevent damage.

  4.  
  5. Remove the gasket. Discard the gasket. Discard the M11 cylinder head bolts.
  6.  

To install:


NOTE
Do not use any type sealant on the cylinder head gasket (unless specified). The cylinder head gaskets must be installed in the proper direction and position.

  1. Clean the engine block cylinder head bolt holes (if required). Thread repair tool J 42385-107 may be used to clean the threads of old thread locking material.
  2.  
  3. Spray cleaner GM P/N 12346139, P/N 12377981, or equivalent into the hole.
  4.  
  5. Clean the cylinder head bolt holes with compressed air.
  6.  
  7. Check the cylinder head locating pins for proper installation.
    NOTE
    When properly installed, the tab on the left cylinder head gasket will be located left of center or closer to the front of the engine.

  8.  
  9. Install or connect the following:

    NEW left cylinder head gasket onto the locating pins
     
    Cylinder head onto the locating pins and the gasket
     
    NEW M11 cylinder head bolts.
     

  10.  
  11. Apply a 0.20 in. (5mm) band of threadlock GM P/N 12345382 or equivalent to the threads of the M8 cylinder head bolts.

    M8 cylinder head bolts
     
    M8 cylinder head bolts.
     

  12.  
  13. Tighten the cylinder head bolts as follows:
    1. M11 bolts (1-10) 1st pass: in sequence to 22 ft. lbs. (30 Nm).
    2.  
    3. M11 bolts (1-10) 2nd pass: in sequence + 90 degrees.
    4.  
    5. M11 bolts (1-10): + 70 degrees.
    6.  
    7. M8 cylinder head bolts (11,12,13,14,15) to 22 ft. lbs. (30 Nm). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.
    8.  

  14.  
  15. Install or connect the following:

    Alternator mounting bracket. Tighten the four bolts to 37 ft. lbs. (50 Nm).
     
    Bolt at the rear of the power steering pump and tighten to 37 ft. lbs. (50 Nm).
     
    Exhaust manifold(s)
     
    Pushrods
     
    Intake manifold
     
    Negative battery cable
     

  16.  

Right Side

CAUTION
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures.

  1. Remove or disconnect the following:
    NOTE
    The M11 cylinder head bolts are NOT reusable. Install NEW M11 cylinder head bolts during reassembly.


    NOTE
    After removal, place the cylinder head on two wood blocks to prevent damage.



    Negative battery cable
     
    Coolant air bleed pipe
     
    Intake manifold
     
    Push rods
     
    Exhaust manifold(s)
     
    Alternator
     
    Alternator mounting bracket-to-cylinder head bolts
     
    Bolt behind the power steering pump
     
    Alternator mounting bracket and set it aside
     
    Bolt holding the oil level indicator tube to the right side cylinder head
     
    Oil level indicator tube
     
    Cylinder head(s) from the engine
     
    Spark plugs
     
    Cylinder head bolts
     

  2.  
  3. Remove the gasket. Discard the gasket. Discard the M11 cylinder head bolts.
  4.  

To install:


NOTE
Do not use any type sealant on the cylinder head gasket (unless specified). The cylinder head gaskets must be installed in the proper direction and position.

  1. Clean the engine block cylinder head bolt holes (if required). Thread repair tool J 42385-107 may be used to clean the threads of old threadlocking material.
  2.  
  3. Spray cleaner GM P/N 12346139, P/N 12377981, or equivalent into the hole.
  4.  
  5. Clean the cylinder head bolt holes with compressed air.
  6.  
  7. Check the cylinder head locating pins for proper installation.
    NOTE
    When properly installed, the tab on the right cylinder head gasket will be located right of center or closer to the front of the engine.

  8.  
  9. Install or connect the following:
    NOTE
    First design engine blocks have different drill and tap depths using both medium length 3.94 inch (100mm) and long 6.1 inch (155mm) M11 cylinder head bolts. Second design engine blocks use only the medium length 3.94 inch (100mm) bolt with a common drill and tap depth.



    NEW right cylinder head gasket onto the locating pins
     
    Cylinder head onto the locating pins and the gasket
     
    NEW M11 cylinder head bolts. Apply a 0.20 in. (5mm) band of threadlock GM P/N 12345382 or equivalent to the threads of the M8 cylinder head bolts.
     



    M8 cylinder head bolts.
     

  10.  
  11. Tighten the first design cylinder head bolts as follows:
    1. M11 bolts 1st pass: in sequence to 22 ft. lbs. (30 Nm).
    2.  
    3. M11 bolts 2nd pass: in sequence + 90 degrees.
    4.  
    5. M11 bolts (1,2,3,4,5,6,7,8): + 90 degrees.
    6.  
    7. M11 bolts (9 and 10): + 50 degrees.
    8.  
    9. M8 cylinder head bolts (11,12,13,14,15) to 22 ft. lbs. (30 Nm). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.
    10.  

  12.  
  13. Tighten the second design cylinder head bolts as follows:
    1. M11 bolts (1-10) 1st pass: in sequence to 22 ft. lbs. (30 Nm).
    2.  
    3. M11 bolts (1-10) 2nd pass: in sequence + 90 degrees.
    4.  
    5. M11 bolts (1-10): + 70 degrees.
    6.  
    7. M8 cylinder head bolts (11,12,13,14,15) to 22 ft. lbs. (30 Nm). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.
      NOTE
      The cylinder head gasket displacement can be verified by markings visible on the underside of the right gasket locating tab. Some 4.8/5.3L head gaskets may have 53 stamped onto the locating tab. Some 6.0L head gaskets may have 60 stamped onto the locating tab.



      Click image to see an enlarged view

      Fig. Locating tab-4.8L, 5.3L and 6.0L engines



      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-4.8L, 5.3L and 6.0L engines

    8.  

  14.  
  15. Install or connect the following:

    Alternator
     
    Exhaust manifold(s)
     
    Pushrods
     
    Intake manifold
     
    Negative battery cable
     

  16.  


CAUTION
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures.

  1. Remove or disconnect the following:
    NOTE
    The M11 cylinder head bolts are NOT reusable. Install NEW M11 cylinder head bolts during reassembly.


    NOTE
    After removal, place the cylinder head on two wood blocks to prevent damage.



    Negative battery cable
     
    Coolant air bleed pipe
     
    Intake manifold
     
    Push rods
     
    Exhaust manifold(s)
     
    Alternator
     
    Alternator mounting bracket-to-cylinder head bolts
     
    Bolt behind the power steering pump
     
    Alternator mounting bracket and set it aside
     
    Bolt holding the oil level indicator tube to the right side cylinder head
     
    Oil level indicator tube
     
    Cylinder head(s) from the engine
     
    Spark plugs
     



    Cylinder head bolts
     

  2.  
  3. Remove the gasket. Discard the gasket. Discard the M11 cylinder head bolts.
  4.  

To install:


NOTE
Do not use any type sealant on the cylinder head gasket (unless specified). The cylinder head gaskets must be installed in the proper direction and position.

  1. Clean the engine block cylinder head bolt holes (if required). Thread repair tool J 42385-107 may be used to clean the threads of old thread locking material.
  2.  
  3. Spray cleaner GM P/N 12346139, P/N 12377981, or equivalent into the hole.
  4.  
  5. Clean the cylinder head bolt holes with compressed air.
  6.  
  7. Check the cylinder head locating pins for proper installation.
    NOTE
    When properly installed, the tab on the right cylinder head gasket will be located right of center or closer to the front of the engine.

  8.  
  9. Install or connect the following:

    NEW right cylinder head gasket onto the locating pins
     
    Cylinder head onto the locating pins and the gasket
     
    NEW M11 cylinder head bolts. Apply a 0.20 in. (5mm) band of threadlock GM P/N 12345382 or equivalent to the threads of the M8 cylinder head bolts.
     
    M8 cylinder head bolts.
     

  10.  
  11. Tighten the cylinder head bolts as follows:
    1. M11 bolts (1-10) 1st pass: in sequence to 22 ft. lbs. (30 Nm).
    2.  
    3. M11 bolts (1-10) 2nd pass: in sequence + 90 degrees.
    4.  
    5. M11 bolts (1-10): + 70 degrees.
    6.  
    7. M8 cylinder head bolts (11,12,13,14,15) to 22 ft. lbs. (30 Nm). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.

      Click image to see an enlarged view

      Fig. Locating tab-4.8L, 5.3L and 6.0L engines



      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-4.8L, 5.3L and 6.0L engines

    8.  

  12.  
  13. Install or connect the following:

    Alternator
     
    Exhaust manifold(s)
     
    Pushrods
     
    Intake manifold
     
    Negative battery cable
     

  14.  

5.0L And 5.7L Engines
  1. Drain the coolant.
  2.  
  3. Remove or disconnect the following:

    Negative battery cable
     
    Engine cover
     
    Coolant recovery reservoir, if applicable
     
    Intake manifold
     
    Exhaust manifolds and position them out of the way
     
    Ground strap at the rear of the right AIR pipe, if equipped
     

  4.  
  5. For vans with A/C, remove the A/C compressor and the forward mounting bracket and lay the compressor aside. Do not disconnect any of the refrigerant lines.

    Exhaust Gas Recirculation (EGR) inlet tube
     

  6.  
  7. On the right side cylinder head, disconnect the fuel pipe, spark plug wires and wiring harness bracket.
    NOTE
    You may have to loosen the remaining bolts and studs in order to remove the head.



    Nut and stud attaching the main accessory bracket to the cylinder head
     



    Coolant sensor wire
     
    Spark plug wire bracket
     
    Cylinder head covers
     
    Spark plugs
     
    Pushrods. Identify the pushrods so that they can be installed in their original positions.
     
    Cylinder head bolts in the reverse order of the tightening sequence
     
    Heads
     

  8.  

To install:

  1. Inspect the cylinder head and block mating surfaces. Clean all old gasket material.
  2.  
  3. Install or connect the following:
    NOTE
    Coat a steel gasket on both sides with sealer. If a composition gasket is used, do not use sealer.



    Cylinder heads using new gaskets. Install the gaskets with the word HEAD up.
     

  4.  
  5. Clean the bolts, apply sealer to the threads, and hand-tighten.
  6.  
  7. Install the cylinder head bolts in sequence to 22 ft. lbs. (30 Nm). The bolts must be tightened once, then be tightened again in sequence in the following order:
    1. Step 1: Short length bolt: (3, 4, 7, 8, 11, 12, 15, 16), plus 55 degrees.
    2.  
    3. Step 2: Medium length bolt: (14, 17), plus 65 degrees.
    4.  
    5. Step 3: Long length bolts: (1, 2, 5, 6, 9, 10, 13), plus 75 degrees.

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-5.0L and 5.7L engines

    6.  

  8.  
  9. Install or connect the following:

    Pushrods in their original positions
     
    Cylinder head covers
     
    Spark plugs
     
    Coolant sensor wire
     
    Spark plug wire bracket
     
    Main accessory bracket to the cylinder head
     
    EGR vent tube
     
    Fuel pipe
     
    Spark plug wires
     
    Wiring harness bracket
     
    A/C compressor and forward mounting bracket
     
    Ground strap to the rear of the right AIR pipe
     
    Exhaust manifolds
     
    Intake manifold
     
    Coolant recovery reservoir, if removed
     
    Engine cover
     
    Negative battery cable
     

  10.  
  11. Refill the engine with coolant.
  12.  

6.5L Engine
  1. Relieve the fuel system pressure.
  2.  
  3. Drain the coolant system.
  4.  
  5. Discharge the air conditioning system.
  6.  
  7. Remove or disconnect the following:
    NOTE
    Mark all components so they may be returned to their original location.



    Negative battery cables
     
    Intake manifold
     
    Fan upper shroud
     
    Compressor assembly, if equipped
     
    Turbocharger, if equipped
     
    Exhaust manifold
     
    Valve cover
     
    Rocker arm assemblies and pushrods
     



    Air cleaner resonator and bracket
     
    Transmission and oil dipstick tube; remove the oil fill tube from the coolant crossover pipe
     
    Heater, radiator and bypass hoses
     
    Alternator upper bracket
     
    Alternator
     
    Power steering pump
     
    Vacuum pump
     
    Fuel bleeder valve at the coolant crossover pipe
     
    Fuel return crossover line clamp bolts from both cylinder heads
     
    Wire connector from the sensor in the coolant crossover pipe
     
    Electrical connection and brackets from cylinder head
     
    Coolant crossover pipe/thermostat assembly
     
    Head bolts and the cylinder heads
     

  8.  

To install:

  1. Clean the mating surfaces of the heads and block thoroughly.
  2.  
  3. Clean the head bolts thoroughly. Coat the threads of the head bolts with sealing compound GM part 1052080 or equivalent, before installation.

    Click image to see an enlarged view

    Fig. Tighten the cylinder head bolts according to the sequence shown for proper cylinder sealing-6.5L diesel engines

  4.  
  5. Install a new gaskets, and the cylinder head and bolts. Torque the bolts, in sequence, as follows:
    1. Step 1: 20 ft. lbs. (25 Nm)
    2.  
    3. Step 2: 50 ft. lbs. (65 Nm).
    4.  
    5. Step 3: An additional 90 degrees ( 1 / 4 turn).
    6.  

  6.  
  7. Install or connect the following:

    Coolant crossover pipe and thermostat
     
    Fuel valve
     
    Bypass hose
     
    Upper radiator hose
     
    Heater hoses at the head
     
    Transmission and oil dipstick tube
     
    Air cleaner resonator and bracket
     
    Pushrods, hardened ends facing up
     
    Rocker arm assemblies
     

  8.  
  9. Adjust the valves.

    Valve cover
     
    Alternator and upper bracket
     
    Exhaust manifolds. Torque bolts to 22 ft. lbs. (30 Nm).
     
    Upper fan shroud
     
    Intake manifold
     
    Turbocharger, if equipped
     
    Vacuum pump, if equipped
     
    Air conditioning compressor, if equipped
     
    Engine electrical connection
     
    Negative battery cables
     

  10.  
  11. Refill the cooling system with the proper type and quantity of antifreeze.
  12.  
  13. Evacuate and recharge the air conditioning system.
  14.  

6.6L Engine
  1. Relieve the fuel system pressure.
  2.  
  3. Drain the coolant system.
  4.  
  5. Remove or disconnect the following:

    Negative battery cables
     
    Left or right front splash shield from the fender well, as applicable
     
    Turbocharger
     
    Turbocharger charged air cooler inlet duct
     
    Thermostat housing crossover
     
    Left or right intake manifold, as necessary
     
    Upper left or right valve cover
     
    Fuel rail assembly
     
    Left or right exhaust manifold
     
    Bolt and ground straps from the rear of the cylinder head
     
    Lower left or right valve cover
     
    Rocker arm shaft assembly
     
    Glow plugs
     
    Fuel injector return pipe eye bolts and washers
     
    Fuel injector return pipe assembly
     
    Fuel injector bracket bolts
     
    Fuel injectors with the brackets, using a suitable removal tool
     
    Injector bracket pins
     
    Cylinder head bolts, in the proper sequence
     
    Cylinder head and gasket. Discard the gasket

    Click image to see an enlarged view

    Fig. Cylinder head bolt loosening sequence-6.6L engines

     

  6.  

To install:

  1. Clean the mating surfaces of the heads and block thoroughly.
  2.  
  3. Position a new left or right side head gasket on the block. Note that the left and right side gaskets are NOT interchangeable.
    NOTE
    The cylinder head bolts on these vehicles are pre-coated with an application of a molybdenum disulfide for thread lubrication. Do not remove the coating or add any additional lubrication.

  4.  
  5. Install the cylinder head and bolts.
  6.  
  7. Tighten the cylinder head bolts, in sequence, as follows:
    1. Step 1: M12 bolts to 37 ft. lbs. (50 Nm).
    2.  
    3. Step 2: M12 bolts to 59 ft. lbs. (80 Nm).
    4.  
    5. Step 3: Using a torque angle meter, tighten the M12 bolts an additional 60 degrees.
    6.  
    7. Step 4: Using a torque angle meter, tighten the M12 bolts an additional 60 degrees.
    8.  
    9. Step 5: M8 bolts to 18 ft. lbs. (25 Nm).

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-6.6L engines

    10.  

  8.  
  9. Install or connect the following:
    NOTE
    If you are reusing the old injectors, clean the carbon from the tips, but do not use a wire brush.



    New O-ring onto the fuel injectors after coating with clean engine oil
     
    New copper washer into the fuel injector bore in the cylinder head
     
    Fuel injector bracket pin
     



    Fuel injector bracket bolt and tighten to 37 ft. lbs. (50 Nm)
     
    Fuel injector return pipe assembly
     
    Fuel injector return pipe-to-injector eye bolts and washers. Tighten to 11 ft. lbs. (15 Nm).
     
    Fuel return pipe-to-cylinder head eye bolts and washers. Tighten to 11 ft. lbs. (15 Nm).
     
    Bolt and ground straps to the rear of the cylinder head. Tighten to 18 ft. lbs. (25 Nm).
     
    Valve rocker shaft assembly
     
    Lower and upper valve covers
     
    Glow plugs
     
    Exhaust manifold
     
    Fuel rail assembly
     
    Intake manifold
     
    Thermostat housing crossover
     
    Turbocharger charged air cooler duct
     
    Clamp and hose to the charged air cooler. Tighten to 53 inch lbs. (6 Nm).
     
    Turbocharger
     
    Fender splash shield
     
    Negative battery cables
     

  10.  
  11. Refill the cooling system with the proper type and quantity of antifreeze.
  12.  
  13. Evacuate and recharge the air conditioning system.
  14.  

7.4L Engines
  1. Before servicing the vehicle, refer to the Precautions section.
  2.  
  3. Drain the cooling system.
  4.  
  5. Remove or disconnect the following:

    Negative battery cable
     
    Engine cover
     
    Intake manifold
     
    Exhaust manifolds
     
    Alternator and bracket
     
    Air pump, if equipped
     
    Air conditioning compressor and the forward mounting bracket. Do not disconnect any of the refrigerant lines.
     
    Rocker arm cover
     
    Spark plugs
     
    Air pipes at the rear of the head, if equipped
     
    Ground strap at the rear of the head
     
    Temperature sensor wire
     
    Pushrods. Identify the pushrods so that they can be installed in their original positions.
     
    Cylinder head bolts and the heads
     

  6.  

To install:


NOTE
The cylinder head should be cleaned and inspected for warpage or damage before installation.

  1. Thoroughly clean the mating surfaces of the head and block. Clean the bolt holes thoroughly.
    NOTE
    Coat a steel gasket on both sides with sealer. If a composition gasket is used, do not use sealer.

  2.  
  3. Install or connect the following:

    New gaskets, with the word HEAD up
     
    Cylinder heads
     

  4.  
  5. Apply sealer to the threads of the head bolts, then install and tighten in sequence, in 3 stages, as follows:
    1. Step 1: 30 ft. lbs. (40 Nm).
    2.  
    3. Step 2: 60 ft. lbs. (80 Nm).
    4.  
    5. Step 3: 85 ft. lbs. (115 Nm).

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-7.4L engines



      Intake and exhaust manifolds
       
      Pushrods
       
      Rocker arms
       
      Temperature sensor wire
       
      Ground strap at the rear of the head
       
      AIR pipes at the rear of the head
       
      Spark plugs
       
      Rocker arm cover
       
      Air conditioning compressor and forward mounting bracket
       
      AIR pump
       
      Alternator
       
      Engine cover
       

    6.  

  6.  
  7. Connect the battery cable and refill the cooling system.
  8.  

8.1L Engine
Left Side
  1. Drain the cooling system.
  2.  
  3. Remove or disconnect the following:

    Negative battery cable
     
    Water crossover
     
    Intake manifold
     
    Valve cover
     
    Rocker arms and pushrods, keeping them in order for installation
     
    Engine harness ground bolts
     

  4.  
  5. Reposition the engine harness grounds and ground straps from the cylinder head.
    NOTE
    The cylinder head bolts must be replaced for installation.



    Exhaust manifold
     
    Cylinder head bolts, then discard
     



    Cylinder head. Place the head on 2 wood blocks to protect the sealing surfaces while it is removed.
     

  6.  

To install:


NOTE
The cylinder head should be cleaned and inspected for warpage or damage before installation.

  1. Thoroughly clean the mating surfaces of the head and block. Clean the bolt holes thoroughly.
    NOTE
    If a composition gasket is used, do not use sealer.

  2.  
  3. Align the cylinder head gasket locating marks to face up. Make sure that the gasket tabs are located of the No. 1 and 2 cylinder for proper installation.
  4.  
  5. Install or connect the following:
    NOTE
    The long bolts are used in locations 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16, and 17. The medium length bolts are used in locations 15 and 18. The short bolts are used in locations 4, 5, 12, and 13.



    New cylinder head gasket
     
    Cylinder head
     
    Sealer to the threads of new cylinder head bolts, if not pre-applied
     

  6.  
  7. Tighten the head bolts, in sequence, in 4 stages, as follows:
    1. Step 1: 22 ft. lbs. (30 Nm).
    2.  

  8.  
  9. Step 2: 22 ft. lbs. (30 Nm)
    1. Step 3: Additional 120 degrees using a torque angle meter.
    2.  
    3. Step 4: Torque bolt numbers. 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16 and 17 an additional 60 degrees.
    4.  
    5. Tighten bolts 15 and 18 an additional 45 degrees, and bolt numbers 4, 5, 12 and 13 an additional 30 degrees.

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-8.1L engine

    6.  

  10.  
  11. Install or connect the following:

    Exhaust manifold
     
    Water crossover
     
    Engine harness grounds and ground strap
     
    Rocker arms and pushrods
     
    Valve cover
     
    Intake manifold
     

  12.  
  13. Connect the battery cable and refill the cooling system.
  14.  

  1. Drain the cooling system.
  2.  
  3. Remove or disconnect the following:

    Negative battery cable
     
    Water crossover
     
    Intake manifold
     
    Valve cover
     
    Rocker arms and pushrods, keeping them in order for installation
     
    Engine harness ground bolts
     

  4.  
  5. Reposition the engine harness grounds and ground straps from the cylinder head.
    NOTE
    The cylinder head bolts must be replaced for installation.



    Exhaust manifold
     
    Cylinder head bolts, then discard
     



    Cylinder head. Place the head on 2 wood blocks to protect the sealing surfaces while it is removed.
     

  6.  

To install:


NOTE
The cylinder head should be cleaned and inspected for warpage or damage before installation.

  1. Thoroughly clean the mating surfaces of the head and block. Clean the bolt holes thoroughly.
    NOTE
    If a composition gasket is used, do not use sealer.

  2.  
  3. Align the cylinder head gasket locating marks to face up. Make sure that the gasket tabs are located of the No. 1 and 2 cylinder for proper installation.
  4.  
  5. Install or connect the following:
    NOTE
    The long bolts are used in locations 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16, and 17. The medium length bolts are used in locations 15 and 18. The short bolts are used in locations 4, 5, 12, and 13.



    New cylinder head gasket
     
    Cylinder head
     
    Sealer to the threads of new cylinder head bolts, if not pre-applied
     

  6.  
  7. Tighten the head bolts, in sequence, in 4 stages, as follows:
    1. Step 1: 22 ft. lbs. (30 Nm).
    2.  

  8.  
  9. Step 2: 22 ft. lbs. (30 Nm)
    1. Step 3: Additional 120 degrees using a torque angle meter.
    2.  
    3. Step 4: Torque bolt numbers. 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16 and 17 an additional 60 degrees.
    4.  
    5. Tighten bolts 15 and 18 an additional 45 degrees, and bolt numbers 4, 5, 12 and 13 an additional 30 degrees.

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-8.1L engines

    6.  

  10.  
  11. Install or connect the following:

    Exhaust manifold
     
    Water crossover
     
    Engine harness grounds and ground strap
     
    Rocker arms and pushrods
     
    Valve cover
     
    Intake manifold
     

  12.  
  13. Connect the battery cable and refill the cooling system.
  14.  

Right Side
  1. Drain the cooling system.
  2.  
  3. Remove or disconnect the following:
    NOTE
    The cylinder head bolts must be replaced for installation.



    Negative battery cable
     
    Intake manifold
     
    Valve cover
     
    Rocker arms and pushrods, keeping them in order for installation
     
    Engine Coolant Temperature (ECT) sensor clip from the bracket
     
    ECT sensor
     
    ECT sensor bracket bolt and bracket
     
    Heater inlet and outlet hoses from the hose bracket
     
    Water crossover
     
    Exhaust manifold
     
    Cylinder head bolts, then discard
     



    Cylinder head. Place the head on 2 wood blocks to protect the sealing surfaces while it is removed.
     

  4.  

To install:


NOTE
The cylinder head should be cleaned and inspected for warpage or damage before installation.

  1. Thoroughly clean the mating surfaces of the head and block. Clean the bolt holes thoroughly.
    NOTE
    If a composition gasket is used, do not use sealer.

  2.  
  3. Align the cylinder head gasket locating marks to face up. Make sure that the gasket tabs are located of the no. 1 and 2 cylinder for proper installation.
  4.  
  5. Install or connect the following:
    NOTE
    The long bolts are used in locations 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16, and 17. The medium length bolts are used in locations 15 and 18. The short bolts are used in locations 4, 5, 12, and 13.



    New cylinder head gasket
     
    Cylinder head
     
    Sealer to the threads of new cylinder head bolts, if not pre-applied
     

  6.  
  7. Tighten the head bolts, in sequence, in 4 stages, as follows:
    1. Step 1: 22 ft. lbs. (30 Nm).
    2.  

  8.  
  9. Step 2: 22 ft. lbs. (30 Nm)
    1. Step 3: Additional 120 degrees using a torque angle meter.
    2.  
    3. Step 4: Torque bolt numbers. 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16 and 17 an additional 60 degrees.
    4.  
    5. Tighten bolts 15 and 18 an additional 45 degrees, and bolt numbers 4, 5, 12 and 13 an additional 30 degrees.
    6.  

  10.  
  11. Install or connect the following:

    Exhaust manifold
     
    Water crossover
     
    Heater hose bracket and bolts. Tighten the bolts to 37 ft. lbs. (50 Nm).
     
    ECT sensor bracket and bolt. Tighten to 37 ft. lbs. (50 Nm).
     
    ECT sensor
     
    ECT sensor clip
     
    Rocker arms and pushrods
     
    Valve cover
     
    Intake manifold
     

  12.  
  13. Connect the battery cable and refill the cooling system.
  14.  

  1. Drain the cooling system.
  2.  
  3. Remove or disconnect the following:
    NOTE
    The cylinder head bolts must be replaced for installation.



    Negative battery cable
     
    Intake manifold
     
    Valve cover
     
    Rocker arms and pushrods, keeping them in order for installation
     
    Engine Coolant Temperature (ECT) sensor clip from the bracket
     
    ECT sensor
     
    ECT sensor bracket bolt and bracket
     
    Heater inlet and outlet hoses from the hose bracket
     
    Water crossover
     
    Exhaust manifold
     
    Cylinder head bolts, then discard
     



    Cylinder head. Place the head on 2 wood blocks to protect the sealing surfaces while it is removed.
     

  4.  

To install:


NOTE
The cylinder head should be cleaned and inspected for warpage or damage before installation.

  1. Thoroughly clean the mating surfaces of the head and block. Clean the bolt holes thoroughly.
    NOTE
    If a composition gasket is used, do not use sealer.

  2.  
  3. Align the cylinder head gasket locating marks to face up. Make sure that the gasket tabs are located of the no. 1 and 2 cylinder for proper installation.
  4.  
  5. Install or connect the following:
    NOTE
    The long bolts are used in locations 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16, and 17. The medium length bolts are used in locations 15 and 18. The short bolts are used in locations 4, 5, 12, and 13.



    New cylinder head gasket
     
    Cylinder head
     
    Sealer to the threads of new cylinder head bolts, if not pre-applied
     

  6.  
  7. Tighten the head bolts, in sequence, in 4 stages, as follows:
    1. Step 1: 22 ft. lbs. (30 Nm).
    2.  

  8.  
  9. Step 2: 22 ft. lbs. (30 Nm)
    1. Step 3: Additional 120 degrees using a torque angle meter.
    2.  
    3. Step 4: Torque bolt numbers. 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16 and 17 an additional 60 degrees.
    4.  
    5. Tighten bolts 15 and 18 an additional 45 degrees, and bolt numbers 4, 5, 12 and 13 an additional 30 degrees.

      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-8.1L engines

    6.  

  10.  
  11. Install or connect the following:

    Exhaust manifold
     
    Water crossover
     
    Heater hose bracket and bolts. Tighten the bolts to 37 ft. lbs. (50 Nm).
     
    ECT sensor bracket and bolt. Tighten to 37 ft. lbs. (50 Nm).
     
    ECT sensor
     
    ECT sensor clip
     
    Rocker arms and pushrods
     
    Valve cover
     
    Intake manifold
     

  12.  
  13. Connect the battery cable and refill the cooling system.
  14.  

 
label.common.footer.alt.autozoneLogo