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 LS1 engine utilize metric threads. |
| • | Cylinder head, connecting rod, crankshaft balancer, and main bearing
cap bolts now apply a torque angle tightening strategy. |
| • | 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. |
| • | Certain fasteners should not be used again. Bolts, studs, or other fasteners
that must be replaced will be called out in the specific service procedure. |
Changed Engine Specifications
Metric and English values are given for all specifications.
New Sealants and/or Adhesives
Canadian SPO Part Numbers have been added.
Disassembly and Assembly Procedure Revisions
| • | 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 condition. The diagnostic flow is
the place to start when repairs are necessary.
New Special Tools Required
| • | A variety of new tools have been developed to assist in engine disassembly,
assembly and on-vehicle service. |
| • | J 43690 and J 43690-100
have been developed to
measure connecting rod bearing clearances. |
| • | A cylinder leak down test, using J 35667-A
, has been developed. |
| • | J 45299 has been
developed to prelube new or remanufactured engines/bearings prior to engine installation. |
| • | J 45059 has been
developed to ensure fasteners are tightened to true clamp load specifications. |
A Component Comparison from the Previous Year
| • | The engine coolant air bleed system has been changed to a two point system
with the coolant air bleed pipe mounted to the front top area of both cylinder heads. |
| • | 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 the connecting rod. |
| • | The first design press fit piston, pin and connecting rod are to be serviced
as an assembly. |
| • | Certain 2004 applications have a second design piston with a graphite
coated skirt. |
