GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2001 🢒 GMC C Sierra - 2WD 🢒 Engine 🢒 Engine Mechanical - 4.3L 🢒 Oil Pan Replacement

Removal Procedure
  1. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

    3. Object Number: 309158 Size: SH
  3. Remove the oil pan skid plate (RWD shown).
  4. Remove the oil pan drain plug and drain the engine oil into a suitable container.
  5. Remove the oil filter.

    6. Object Number: 328107 Size: SH
  6. Remove the crossbar RWD vehicle.

    7. Object Number: 487521 Size: SH
  7. Remove the crossbar 4WD vehicle.
  8. Remove the front differential carrier assembly, if equipped. Refer to Differential Carrier Assembly Replacement in Front Axle.

    9. Object Number: 310250 Size: SH
  9. Remove the bolts holding the battery cable brackets to the oil pan.
  10. Remove the starter and move aside. Refer to Starter Motor Replacement in Engine Electrical.

    11. Object Number: 391868 Size: SH
  11. Remove the transmission cover.

    12. Object Number: 327996 Size: SH
  12. Remove the bracket for the starter positive cable and the transmission cooler lines form the side of the oil pan.

    13. Object Number: 407501 Size: SH
  13. Disconnect the low oil level sensor electrical connector.

    14. Object Number: 331034 Size: SH
  14. Remove the access plugs for the oil pan rear nuts.

    15. Object Number: 497449 Size: SH
  15. Remove the transmission to oil pan bolts (manual transmission shown).

    16. Object Number: 387460 Size: SH

    Important: The low oil level sensor is not reusable. Use a NEW low oil sensor.

  16. Remove and discard the engine oil level sensor (if applicable).

    17. Object Number: 330559 Size: SH
  17. Remove the oil pan bolts and nuts.

    18. Object Number: 330568 Size: SH
  18. Remove the oil pan.

    19. Object Number: 387757 Size: SH
  19. Remove the oil pan gasket.
  20. Discard the oil pan gasket.
  21. Clean all sealing surfaces on the engine and the oil pan. Refer to Oil Pan Cleaning and Inspection in Engine Unit Repair Manual.

Installation Procedure

    Object Number: 317310 Size: SH

    Notice: Any time the transmission and the engine oil pan are off of the engine at the same time, install the transmission before the oil pan. This is to allow for the proper oil pan alignment. Failure to achieve the correct oil pan alignment can result in transmission failure.

  1. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of adhesive GM P/N 12346141 or equivalent to both the right and left sides of the engine front cover to engine block junction at the oil pan sealing surfaces.

    2. Object Number: 317313 Size: SH
  2. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of adhesive GM P/N 12346141 or equivalent to both the right and left sides of the crankshaft rear oil seal housing to engine block junction at the oil pan sealing surfaces.

    3. Object Number: 387757 Size: SH

    Important: Always install a NEW oil pan gasket.

    The oil pan gasket and oil pan must be installed and the fasteners tightened while the adhesive is still wet to the touch.

  3. Install the NEW oil pan gasket into the groove in the oil pan.

    4. Object Number: 330568 Size: SH

    Important: The oil pan alignment must always be flush or forward no more than 0.3 mm (0.011 in) from the rear face of the engine block.

  4. Install the oil pan onto the engine block.

    5. Press the oil pan gasket into the grooves of the engine front cover and crankshaft rear oil seal housing.

  5. Slide the oil pan back against a suitable straight edge.

    6. Object Number: 38496 Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Install the oil pan bolts and nuts, but do not tighten.
  7. Measure the pan-to-transmission housing clearance using a feeler gauge and a straight edge.

    8. Use a feeler gauge to check the clearance between the oil pan-to-transmission housing measurement points. If the clearance exceeds 0.3 mm (0.011 in) at any of the 3 oil pan-to-transmission housing measurement points (1), then repeat the step until the oil pan-to-transmission housing clearance is within the specification. The oil pan must always be forward of the rear face of the engine block.


    Object Number: 38481 Size: SH
  8. Tighten the oil pan bolts and nuts in sequence (1-12).

    9. Tighten
    Tighten the oil pan bolts to 25 N·m (18 lb ft).

  9. Measure the clearance between the 3 oil pan-to-transmission housing measurement points in order to ensure proper alignment.

    10. Object Number: 188048 Size: SH
  10. Install a NEW oil pan drain plug seal (O-ring) onto the oil pan drain plug.
  11. Install the oil pan drain plug into the oil pan.

    12. Tighten
    Tighten the oil pan drain plug to 25 N·m (18 lb ft).


    Object Number: 387460 Size: SH

    Important: The low oil level sensor is not reusable. Use a NEW low oil sensor.

  12. Install the NEW engine oil level sensor (if applicable).

    13. Tighten
    Tighten the engine oil level sensor to 13 N·m (115 lb in).


    Object Number: 391868 Size: SH
  13. Install the transmission cover.

    14. Tighten
    Tighten the bolts to 12 N·m (106 lb in).


    Object Number: 497449 Size: SH
  14. Install the transmission to oil pan bolts (manual transmission shown).

    15. Tighten
    Tighten the bolts to 47 N·m (35 lb ft).


    Object Number: 331034 Size: SH
  15. Install the access plugs for the oil pan rear nuts,

    16. Object Number: 327996 Size: SH
  16. Install the bracket for the starter positive cable and the transmission cooler lines to the side of the oil pan.

    17. Tighten
    Tighten the bolts to 9 N·m (80 lb in).


    Object Number: 407501 Size: SH
  17. Install the starter. Refer to Starter Motor Replacement in Engine Electrical.
  18. Connect the low oil level sensor electrical connector.

    19. Object Number: 310250 Size: SH
  19. Install the bolts holding the battery cable brackets to the oil pan.

    20. Tighten
    Tighten the bolts to 12 N·m (106 lb in).


    Object Number: 328107 Size: SH
  20. Install the crossbar RWD vehicle.

    21. Tighten
    Tighten the bolts to 100 N·m (74 lb ft).


    Object Number: 487521 Size: SH
  21. Install the front differential carrier assembly, if equipped. Refer to Differential Carrier Assembly Replacement in Front Axle.
  22. Install the crossbar 4WD vehicle.

    23. Tighten
    Tighten the bolts to 100 N·m (74 lb ft).


    Object Number: 309158 Size: SH
  23. Install the oil pan skid plate (RWD shown).

    24. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).


    Object Number: 316766 Size: SH
  24. Lubricate the engine oil filter gasket with clean engine oil.
  25. Install the engine oil filter to the engine.
  26. Follow the tightening instructions on the oil filter.
  27. Lower the vehicle.
  28. Fill the engine with the proper capacity and quality of engine oil. Refer to Approximate Fluid Capacities in Maintenance and Lubrication.
  29. Connect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.