Subject: | Information on Revised Design of Intake Gasket and Related Bolts for 2004 Mid-Year Enhancement and Prior Year Service Usage |
Models: | 2001-2003 Chevrolet Kodiak 4500/5500 |
2001-2004 Chevrolet Siverado, Suburban |
2002-2004 Chevrolet Avalanche |
2001-2003 GMC TopKick 4500/5500 |
2001-2004 GMC Sierra, Yukon XL |
with 8.1L Engine (VINs E, G - RPO L18) |
Changes have been made to the 8.1L engine during the 2004 Model Year. The intake gaskets and bolts have been changed. This change adds locating pins and requires longer bolts as the cylinder head has been updated to accept the pins. All service cylinder heads from GMSPO will be of this updated style. To aid the technician in diagnosis, the color of the intake manifold to cylinder head bolts has been changed from silver to black.
Refer to the following information when servicing an 8.1L engine; gaskets should be ordered based on bolt color:
Intake Bolt Color | Intake Gasket P/N | Bolt P/N |
---|---|---|
Silver - both cylinder heads | 89017539 - without locating pin | 12561518 - 65 mm |
Black - both cylinder heads | 89017343 - with locating pin | 11588980 - 72 mm |
Silver - one cylinder head Black - one cylinder head | 89017539 - without locating pin | 12561518 - 65 mm 11588980 - 72 mm |
Parts are currently available from GMSPO.
If an engine has one side that uses silver bolts and one that uses black bolts, be sure to replace bolts with the same style.
Important: Intake manifold bolts should be replaced any time they are removed for servicing.