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 4.8, 5.3, and 6.0 liter
engines 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. |
New Sealants and/or Adhesives
Canadian SPO Part Numbers have been added.
Changed Engine Specifications
LQ9 6.0L applications have a higher compression ratio. Refer to
Engine Mechanical Specifications
.
Disassembly and Assembly Procedure Revisions
| • | For certain applications, a spacer plate has been added between the flywheel
and rear of the crankshaft. It is necessary to remove the spacer plate prior to
removal and installation of the crankshaft rear oil seal and clutch pilot bearing. |
| • | An Exhaust Gas Recirculation (EGR) system is used on limited applications. |
| • | 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
in Engine Mechanical.
New Special Tools Required
| • | A variety of new tools have been developed to assist in engine disassembly,
assembly, and on-vehicle service. |
| • | J 42078 is not required
for installation of the second design valve stem oil seal and shim assembly. Refer
to
Special Tools
. |
A Component Comparison from the Previous Year
| • | A new 5.3L engine has been developed and is identified as RPO L59 VIN Z. |
| • | A new 6.0L engine has been developed and is identified as RPO LQ9 VIN
N. |
| • | All applications will use a two-point engine coolant air bleed pipe design. |
| • | The Air Injection Reaction (AIR) system had been deleted from all applications. |
| • | A second design valve stem oil seal and shim assembly will be used on
all engines. |
| • | Certain applications use a multi-layer steel design cylinder head gasket. |
| • | 6.0L LQ9 engines will use a full-floating piston and pin design.
In those applications, the pin is retained in the piston by retaining clips. |
