Subject: | 6.6L LB7, LLY Duramax® Diesel Engine Cylinder Head Gasket Missing Thickness Grade Markings - Inspect Block for Stampings |
Models: | 2001-2005 Chevrolet Silverado |
2003-2005 Chevrolet Kodiak C4500/5500 Series |
2001-2005 GMC Sierra |
2003-2005 GMC TopKick C4500/5500 Series |
with 6.6L Duramax® Diesel Engine (VINs D, 1, 2 -- RPOs LB7, LLY) |
A small number of remanufactured engines were built using oversized bore or milled deck gaskets that do not have any thickness grade identification markings. These engines may show up in any model year from 2001-2005 if the vehicle has received an engine replacement.
Inspect the block for stampings (1) indicating cylinder overbore and a milled deck. The overbore gasket accommodates all cylinder bores from 0.010-0.030". All blocks that are milled are also over-bored.
Stamped ID | Cylinder Bore Size (in) | Top Deck (STD or Milled) |
---|---|---|
0S | 0.010 | STD |
0S | 0.020 | STD |
0S | 0.030 | STD |
01M | 0.010 | Milled |
02M | 0.020 | Milled |
0M | 0.030 | Milled |
First generation head gasket crimped construction (1).
Second generation head gasket riveted construction (1).
Important: The gaskets with no thickness grade specifications will be of crimped construction as opposed to riveted construction. These gaskets require a higher torque specification than what is published in SI. Use the following torque specification when servicing an engine using a head gasket of crimped construction.
Refer to Cylinder Head Replacement in SI. Tighten the cylinder head bolts in the following steps using the sequence below:
Tighten
Part Number | Description | Qty |
---|---|---|
97358467 | Gasket, Cyl Hd, (Oversize Bore) - RH | 1 |
97358465 | Gasket, Cyl Hd, (Oversize Bore and Milled Deck) - RH | 1 |
97358468 | Gasket, Cyl Hd, (Oversize Bore) - LH | 1 |
97358466 | Gasket, Cyl Hd, (Oversize Bore and Milled Deck) - LH | 1 |
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
---|---|---|
J0500 | Gasket, Cylinder Head - Right Bank - Replace | Use Published Labor Operation Time |
J0501 | Gasket, Cylinder Head - Left Bank - Replace | |
J0507 | Gasket, Cylinder Head - Both Banks - Replace |