GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1998 🢒 GMC Suburban - 4WD 🢒 Engine 🢒 Engine Mechanical - 6.5L 🢒 Crankshaft Rear Oil Seal Replacement

Removal Procedure

Important: Before a new crankshaft rear oil seal is installed, the CDR and crankshaft ventilation system should be thoroughly inspect and crankshaft pressure should also be checked. Refer to Engine Controls for proper inspection procedures.


    Object Number: 55077 Size: SH
  1. Disconnect the battery negative cables from the batteries. Refer to Battery Cable in Engine Electrical.
  2. Remove the transfer case from the vehicle if equipped.
    3. • For the vehicle equipped with Manual Four Wheel Drive or Selectable Four Wheel Drive, refer to Transfer Case Replacement in Driveline Axle.
    • For vehicles equipped with Auto Four Wheel Drive 2 Speed, refer to Transfer Case Replacement in Driveline Axle.
  3. Remove the transmission from the vehicle.
    4. • For the 4L 80-E automatic transmission, refer to Transmission Replacement in Transmission/Transaxle.
    • For the NV 4500 manual transmission, refer to Transmission Replacement in Transmission/Transaxle.
  4. Remove the clutch assembly if equipped. Refer to Clutch Assembly Replacement in Transmission/Transaxle.
  5. Remove the flywheel from the crankshaft. Refer to Engine Flywheel Replacement .

    6. Important: Use caution as not to damage the sealing area of the crankshaft when removing the crankshaft rear oil seal.

  6. Remove the crankshaft rear oil seal from the engine block.

Installation Procedure

Tools Required

J 39084 Crankshaft Oil Seal Installer

Important: The crankshaft sealing surface must be clean and smooth in order to prevent damaging the crankshaft rear oil seal lip when a new seal is installed.

Because of the crankshaft rear oil seal wear or grooving, the service crankshaft rear oil will be positioned flush with the rear cylinder block surface. The position of the new crankshaft rear oil seal will be controlled by the tool. Positioning the crankshaft rear oil in a new location provides a new surface for the crankshaft rear oil seal to ride on.


    Object Number: 60280 Size: SH

    Important: Use care as not to cause the spring in the crankshaft rear oil seal to unseat itself .

  1. Apply a small amount of clean engine oil to the lips of the crankshaft rear oil seal before installing.
  2. Use the J 39084 to install the crankshaft rear oil seal.
  3. Install the flywheel to the crankshaft. Refer to Engine Flywheel Replacement .
  4. Install the clutch assembly to the flywheel. Refer to Clutch Assembly Replacement in Transmission/Transaxle.
  5. Install the transmission to the vehicle.
    6. • For the 4L 80-E automatic transmission, refer to Transmission Replacement in Transmission/Transaxle.
    • For the NV 4500 manual transmission, refer to Transmission Replacement in Transmission/Transaxle.
  6. Install the transfer case to the transmission.
    7. • For the vehicle equipped with Manual Four Wheel Drive or Selectable Four Wheel Drive, refer to Transfer Case Replacement in Driveline Axle.
    • For vehicles equipped with Auto Four Wheel Drive 2 Speed, refer to Transfer Case Replacement in Driveline Axle.
  7. Lower the vehicle.
  8. Connect the battery negative cables to the batteries. Refer to Battery Cable in Engine Electrical.