GM Service Manual Online
For 1990-2009 cars only

The purpose of New Product Information is to highlight or indicate important changes from the previous model year.

Changes may include one or more of the following items:

    • Torque values and/or fastener tightening strategies
    • Changed engine specifications
    • New sealants and/or adhesives
    • Disassembly and assembly procedure revisions
    • Engine mechanical diagnostic procedure revisions
    • New special tools required
    • A component comparison from the previous year

Torque Values and/or Fastener Tightening Strategies

The engine mechanical fastener tightening specifications have not changed for model year 2004.

Changed Engine Specifications

There are no changes to the engine specifications for 2004.

New Sealants and/or Adhesives

There are no changes to the sealants and/or adhesives used for model year 2004.

Disassembly and Assembly Procedure Revisions

The Lubrication System Priming Procedure has been replaced by the Lubrication Preluber Procedure. A new tool J 45299 has been developed to prime the engine with new clean engine oil.

Engine Mechanical Diagnostic Procedure Revisions

There are no revisions to the engine mechanical diagnostic procedures for 2004.

New Special Tools Required

*A new tool J 45299 has been developed to prime the engine with new clean engine oil.

*Ensure the proper bushing is used in the cylinder head bolt hole thread repair fixture plate. Refer to Thread Repair .

A Component Comparison from the Previous Year

The thread pitch on the M11 cylinder head bolts and the engine block cylinder head bolt holes has been revised for MY2004. Determine the pitch of the threads by using a thread pitch gage or measure the length of the threads of the cylinder head bolt.

*The MY2003 and earlier cylinder head bolts have a pitch of 1.5 mm and the length of the threads are about 48 mm (1.890 in) long.

*New for MY2004 the cylinder head bolts have a pitch of 2.0 mm and the length of the threads are about 67 mm (2.638 in) long.

*The grounding of the ignition coil assembly is assisted through the use of a grounding strap between the camshaft cover and the cylinder head.

*The right side ignition coil assembly has a sight shield cover.

*The fuel injector sight shield has been revised.

*The generator and A/C compressor have been revised.

*The engine block-to-crankcase seal and sealer placement have been revised.

*The AIR valves have been changed from vacuum to electronic operation.

*The exhaust valve head size has increased to 29 mm (1.141 in).