GM Service Manual Online
For 1990-2009 cars only

The purpose of New Product Information is to highlight or indicate important product 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

    • All fasteners and threaded holes on the 6.0 liter engine utilize metric threads.
    • Cylinder head, connecting rod, crankshaft balancer, and main bearing cap bolts now apply a torque angle strategy.
    • Certain fasteners should not be reused. Bolts, studs, or other fasteners that must be replaced will be called out in the specific service procedure.
    • First design engine blocks cylinder head bolts have different torque/angle specifications using both medium length 100 mm (3.94 in) and long 155 mm (6.1 in) M11 cylinder head bolts. Second design engine blocks use only the medium length 100 mm (3.94 in) bolt with a common torque/angle specification.
    • Refer to Fastener Tightening Specifications and Thread Repair Specifications .

Disassembly and Assembly Procedure Revisions

    • Disassembly of the piston, press fit design piston pin, and connecting rod may create scoring or damage to the piston pin and piston pin bore.
    • The piston, pin, and connecting rod are to be serviced as an assembly.
    • Newer design pistons have a graphite coated piston skirt. The coated skirt outside diameter (OD) may be slightly larger than the cylinder bore inside diameter (ID) and the piston assembly may have a slight interference fit to the cylinder bore during initial installation.

Engine Mechanical Diagnostic Procedure Revisions

All diagnosis on a vehicle should follow a logical process. Strategy based diagnostics is a uniform approach for repairing all systems. The diagnostic flow may always be used in order to resolve a system problem. The diagnostic flow is the place to start when repairs are necessary. For a detailed explanation, refer to Strategy Based Diagnosis in General Information or Diagnostic Starting Point - Engine Mechanical .

New Special Tools Required

Angle Meter J 45059 has been developed to provide technicians with a convenient method to tighten bolts that require the torque angle tightening strategy.

A Component Comparison from the Previous Year

    • Exhaust gas recirculation (EGR) system has been deleted on all applications.
    • All 2004 applications use a piston with a graphite-coated skirt.
    • The positive crankcase ventilation (PCV) valve is a non-serviceable fitting in the left rocker arm cover.
    • The fuel rails for all engines are returnless fuel systems. The fuel pressure regulator is now a part of the fuel pump module.
    • First design applications use a piston pin that is floating fit to the piston and press fit to the connecting rod. Second design applications use a piston pin that is full-floating to both the piston and connecting rod.
    • The first design piston, pin, and connecting rod are to be serviced as an assembly.