Escalade, Suburban 1500 & 2500, Tahoe, Yukon, Yukon XL 1500 & 2500 (2006-2007), Yukon Denali and Yukon Denali XL (2005-2006)

Cylinder Head

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Removal & Installation



4.8L, 5.3L, 6.0L & 6.2L 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 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 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, 6.0L and 6.2L engines



      Click image to see an enlarged view

      Fig. Cylinder head bolt tightening sequence-4.8L, 5.3L, 6.0L and 6.2L engines

    8.  

  12.  
  13. Install or connect the following:

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

  14.  

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 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.  

 
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