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 1 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.

Changed Engine Specifications

No changes to the engine specifications.

Disassembly and Assembly Procedure Revisions

A new design inverted-lip crankshaft rear oil seal is now used. Refer to Crankshaft Rear Oil Seal 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 condition. The diagnostic flow is the place to start when repairs are necessary. For a detailed explanation, refer to Strategy Based Diagnosis or Diagnostic Starting Point - Engine Mechanical.

New Special Tools Required

Oil pressure gage adapter EN-47971 is now required for oil pressure testing. The new design oil filter with internal bypass valve requires a larger diameter oil filter fitting.

A Component Comparison from the Previous Year

    • The oil filter bypass valve is now internal to the oil filter.
    • A new design inverted-lip crankshaft rear oil seal is now used.