Excessive Oil Consumption - keywords bolt gasket head intake
| Subject: | Excessive Oil Consumption |
| Models: | 2002-2005 Chevrolet Avalanche |
| 2001-2005 Chevrolet Silverado, Suburban |
| 2003-2005 Chevrolet Kodiak |
| 2001-2005 GMC Sierra, Yukon XL |
| 2003-2005 GMC TopKick |
| Equipped with 8.1 engine |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Higher than expected oil consumption even after the intake bolts were replaced per Bulletin 02-06-01-035.
Recommendation/Instructions:
Since this type of engine may be used under various load conditions, the acceptable rate of oil consumption is 1 quart (.946L) of oil every 100 gallons (379L) of gasoline. If the intake bolts were replaced per 02-06-01-035 and the excessive oil consumption still exists, replace the intake gaskets with part number 89017539. Use current SI instructions for intake gasket replacement and torque procedures.
Mid year 2004 changes to the cylinder head and intake gaskets were made, making a more robust seal between the cylinder head and the intake manifold. Early 2004 8.1L engines will accept the updated gaskets discussed in this PI, 89017539. The late 2004 8.1L engines that have the updated head and intake gaskets do not require a updated gasket. The differences in the engine are as follows.
2001 to 2004 1/2 8.1L L18 engines will accept the gasket Part Number 89017539.
These engines can be identified by inspecting the intake bolts or the intake gasket.
| • | The intake manifold bolts will be silver in color and measure 65mm long. |
| • | The intake gasket will be flat with no type of locator that engage to the cylinder head |
2004 1/2 to current 8.1L L18 engines will not accept gasket Part Number 89017539.
These engines can also be identified by inspecting the intake bolts or the intake gasket
| • | The intake manifold bolts are black in color and measure 72mm long. |
| • | The intake gaskets are stamped seal with locating Dowels that fit into the counter bored bolt holes in the cylinder head for the intake bolts. |
| • | Due to the more robust intake seal be sure to complete normal oil consumption testing. If oil consumption is excessive (more then 1 quart (.946L) of oil every 100 gallons (379L) of gasoline), complete SI diagnostics for oil consumption |
| • | If a intake gasket is found to be leaking, use the most current parts catalog listings. |
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
