Oil Pan Cleaning and Inspection

Important: 

• Do not use the oil pan gaskets again. Install NEW gaskets during assembly.
• When installing a NEW oil pan gasket, it is not necessary to install the rivets that retain the NEW gasket to the pan.

1. Remove the oil level sensor from the pan.
   Fig 1: Removing Oil Level Sensor From Pan

   Courtesy of GENERAL MOTORS CORP.
2. Remove the oil temperature sensor, oil pan cover, gasket, and bolts.
   Fig 2: Removing Oil Temperature Sensor, Oil Pan Cover, Gasket, And Bolts

   Courtesy of GENERAL MOTORS CORP.
3. Remove the oil pan drain plug and O-ring seal.
   Fig 3: Removing Oil Pan Drain Plug And O-Ring Seal

   Courtesy of GENERAL MOTORS CORP.
4. Drill (3) out the oil pan gasket retaining rivets (2), if required.
   Fig 4: Drilling Out Oil Pan Gasket Retaining Rivets

   Courtesy of GENERAL MOTORS CORP.
5. Remove the oil pan gasket (1).
6. Discard the gasket.
7. Remove the oil pan - lower - bolts (1-15).
   Fig 5: Locating Oil Pan - Lower - Bolts

   Courtesy of GENERAL MOTORS CORP.
8. Separate the oil pan (1) - upper, gasket (2), oil pan (3) - lower, and bolts (4).
   Fig 6: Separating Oil Pan - Upper, Gasket, Oil Pan - Lower, And Bolts

   Courtesy of GENERAL MOTORS CORP.
9. Discard the oil pan gasket.
10. Clean the oil pan halves in solvent. Be sure to thoroughly clean all of the oil passages and recesses of dirt and debris.
    Fig 7: Cleaning Oil Pan Components

    Courtesy of GENERAL MOTORS CORP.
11. Clean the oil pan gasket surfaces. Refer to REPLACING ENGINE GASKETS  .
    CAUTION: Refer to SAFETY GLASSES CAUTION .
12. Dry the oil pan with compressed air.
13. Inspect the gasket sealing surfaces for excessive scratches or gouging. Refer to REPLACING ENGINE GASKETS  .
14. Inspect the oil pan oil level sensor seal surface damage.

    The O-ring seal of the sensor may be used again if it is not cut or damaged.

    Fig 8: Inspecting Oil Pan Oil Level Sensor Seal Surface Damage

    Courtesy of GENERAL MOTORS CORP.
15. Inspect the oil pan drain plug and threaded drain hole for damaged threads.

    The drain plug O-ring seal may be used again if it is not cut or damaged.

    Fig 9: Inspecting Oil Pan Drain Plug And Threaded Drain Hole

    Courtesy of GENERAL MOTORS CORP.
16. Inspect the oil filter and pan cover sealing surface for scratches or gouging.
17. Inspect the oil passages for restrictions.
    Fig 10: Inspecting Oil Filter And Pan Cover Sealing Surface

    Courtesy of GENERAL MOTORS CORP.
18. Inspect the oil filter fitting (1) for a loose fit or damaged threads.
19. Inspect the oil filter bypass valve (2) for proper operation.

    Lightly push the bypass valve into the bore. The valve spring should seat the valve to the proper position.

    Fig 11: Inspecting Oil Filter Fitting

    Courtesy of GENERAL MOTORS CORP.