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

Rocker Arms

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Removal & Installation



4.8L, 5.3L And 6.0L Engines

NOTE
Do not remove the ignition coils from the valve rocker arm cover unless required. Do not remove the oil fill tube from the cover unless service is required. If the oil fill tube has been removed from the cover, install a NEW tube during assembly.

On the right side:

Click image to see an enlarged view

Fig. Rocker arm removal-4.8L, 5.3L and 6.0L engines

  1. Remove or disconnect the following:

    Ignition coil bracket bolts from the rocker arm cover, if required
     
    Ignition coil and bracket assembly from the cover
     
    Valve rocker arm cover bolts
     
    Valve rocker arm cover
     
    Gasket from the cover. Discard the gasket. The bolt grommets may be reused if not damaged.
     
    Oil fill cap from the oil fill tube
     
    Oil fill tube, if required. Discard the oil fill tube.
     

  2.  

On the left side:


NOTE
Do not remove the Positive Crankcase Ventilation (PCV) valve grommet from the cover unless service is required.

  1. Remove or disconnect the following:

    Ignition coil bracket bolts from the rocker arm cover (if required)
     
    Ignition coil and bracket assembly from the cover
     
    Valve rocker arm cover bolts
     
    Valve rocker arm cover
     
    Gasket from the cover. Discard the gasket. The bolt grommets may be reused if not damaged.
     
    Valve rocker arm bolts
     
    Valve rocker arms
     
    Valve rocker arm pivot support
     
    Pushrods
     

  2.  

To install:


NOTE
Valve lash is built in. No valve adjustment is required.

  1. Lubricate the valve rocker arms and pushrods with clean engine oil.
  2.  
  3. Lubricate the flange of the valve rocker arm bolts with clean engine oil.
  4.  
  5. Lubricate the flange or washer surface of the bolt that will contact the valve rocker arm.
  6.  
  7. Install or connect the following:
    NOTE
    Make sure that the pushrods seat properly to the valve lifter sockets.


    NOTE
    Make sure that the pushrods seat properly to the ends of the rocker arms.



    Valve rocker arm pivot support
     



    Pushrods
     



    Rocker arms and bolts. DO NOT tighten the rocker arm bolts at this time
     

  8.  
  9. Rotate the crankshaft until number one piston is at top dead center of compression stroke. In this position, cylinder number one rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. If viewing from the rear of the engine, the additional crankshaft pilot hole (non-threaded) will be in the 10:30 position. The engine firing order is 1, 8, 7, 2, 6, 5, 4, 3. Cylinders 1, 3, 5 and 7 are left bank. Cylinders 2, 4, 6, and 8 are right bank.
  10.  
  11. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
    1. Tighten exhaust valve rocker arm bolts 1, 2, 7, and 8 to 22 ft. lbs. (30 Nm).
    2.  
    3. Tighten intake valve rocker arm bolts 1, 3, 4, and 5 to 22 ft. lbs. (30 Nm).
    4.  

  12.  
  13. Rotate the crankshaft 360 degrees. Tighten the following valve rocker arm bolts:
    1. Tighten exhaust valve rocker arm bolts 3, 4, 5, and 6 to 22 ft. lbs. (30 Nm).
    2.  
    3. Tighten intake valve rocker arm bolts 2, 6, 7, and 8 to 22 ft. lbs. (30 Nm).
    4.  

  14.  

On the right side:


NOTE
The valve rocker arm cover bolt grommets may be reused. If the oil fill tube has been removed from the valve rocker arm cover, install a NEW oil fill tube during assembly.

  1. Lubricate the O-ring seal of the NEW oil fill tube with clean engine oil.
  2.  
  3. Install or connect the following:

    NEW oil fill tube into the rocker arm cover and rotate the tube clockwise until locked in the proper position
     
    Oil fill cap into the tube and rotate clockwise until locked in the proper position
     
    NEW cover gasket into the valve rocker arm cover
     
    Valve rocker arm cover onto the cylinder head
     

  4.  
  5. Install the cover bolts with grommets. Tighten the valve rocker arm cover bolts to 106 inch lbs. (12 Nm).
  6.  
  7. Apply threadlock GM P/N 12345382 or equivalent to the threads of the bracket bolts. Install the ignition coil and bracket assembly and bolts. Tighten the ignition coil and bracket assembly studs to 106 inch lbs. (12 Nm).
  8.  

On the left side:


NOTE
DO NOT reuse the valve rocker arm cover gasket. The valve rocker arm cover bolt grommets may be reused. If the vapor vent grommet has been removed from the valve rocker arm cover, install a NEW vapor vent gourmet during assembly.

  1. Install or connect the following:

    NEW cover gasket (1) into the valve rocker arm cover
     
    Valve rocker arm cover onto the cylinder head
     

  2.  
  3. Install the cover bolts with grommets. Tighten the valve rocker arm cover bolts to 106 inch lbs. (12 Nm).
  4.  
  5. Apply threadlock GM P/N 12345382 or equivalent to the threads of the bracket bolts. Install the ignition coils and bracket assembly and bolts. Tighten the ignition coil and bracket assembly bolts to 106 inch lbs. (12 Nm).
  6.