GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2002 🢒 TrailBlazer - 2WD 🢒 Engine 🢒 Engine Mechanical - 4.2L 🢒 Oil Pan Replacement

Removal Procedure
  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.

    2. Object Number: 735963 Size: SH
  2. Remove the A/C compressor bottom bolts (4) and loosen the top bolts (2, 3).
  3. Remove the oil level indicator and tube. Refer to Oil Level Indicator and Tube Replacement .

    4. Object Number: 893104 Size: SH
  4. Remove the front differential and secure to the frame. Refer to Differential Carrier Assembly Replacement In Front Drive Axle.
  5. Remove the front drive axle intermediate shaft bearing assembly. Refer to Front Drive Axle Intermediate Shaft Bearing Assembly Replacement in Front Drive Axle.
  6. Drain the engine oil. Refer to Engine Oil and Oil Filter Replacement .

    7. Object Number: 754348 Size: SH
  7. Unclip the transmission cooler lines from the engine block.
  8. Remove 4 transmission bell housing bolts that are attached to the oil pan.

    9. Object Number: 1356495 Size: SH
  9. Remove the remaining oil pan bolts.
  10. Place 2 oil pan bolts in the jack screws on the oil pan and tighten evenly to release the oil pan from the engine (1).
  11. Clean and inspect the oil pan. Refer to Oil Pan Cleaning and Inspection .

Installation Procedure

    Object Number: 637715 Size: SH

    Important: The oil pan must be installed within 10 minutes from when sealer was applied

  1. Apply a 3 mm (0.12 in) bead of sealer GM PN 12378521 to the block, rather than the oil pan.

    2. Important: When you install the oil pan, it could be shifted front or back a little which could cause a transmission alignment problem. The back of the oil pan needs to be flush with the block.

  2. Install the oil pan, maneuvering the oil pan to clear the oil pump and screen assembly.
  3. Install the oil pan bolts.

    4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 715595 Size: SH
  4. Inspect the oil pan alignment. Use a straight edge on the back of the block and the oil pan transmission mounting surface.

    5. Tighten

        • Tighten the oil pan side bolts to 25 N·m (18 lb ft).
        • Tighten the oil pan end bolts to 10 N·m (89 lb in).
  5. Install the 4 transmission bell housing bolts that attach to the oil pan.

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


    Object Number: 754348 Size: SH
  6. Clip transmission cooler lines to the engine block.
  7. Install the front drive axle intermediate shaft bearing assembly. Refer to Front Drive Axle Intermediate Shaft Bearing Assembly Replacement in Front Drive Axle.
  8. Install the oil drain plug and filter. Refer to Engine Oil and Oil Filter Replacement .

    9. Object Number: 893104 Size: SH
  9. Install the front differential to the engine. Refer to Differential Carrier Assembly Replacement In Front Drive Axle.

    10. Object Number: 735963 Size: SH
  10. Install the A/C compressor 2 bottom bolts (4).

    11. Tighten
    Tighten all 4 bolts (2-4) to 50 N·m (37 lb ft).

  11. Install the oil level indicator and tube. Refer to Oil Level Indicator and Tube Replacement .
  12. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.

    13. Important: Inspect the engine for oil leaks in order to ensure all sealing surfaces are sealed.

  13. Fill the engine with oil. Refer to Engine Oil and Oil Filter Replacement