Flexplate/Torque Converter Vibration Test (8.1L)

To determine and correct a torque converter vibration, use the following general procedure to achieve the best possible torque converter-to-flywheel balance. Refer to Transmission Replacement (With 8.1L (L18) Engine) for detailed procedure steps as appropriate.

1. Disconnect the battery.
2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle .
3. Remove the starter motor bolts and position the starter motor aside. Refer to Starter Motor Replacement (8.1L Engine) .
4. Remove the converter housing inspection cover.
   Fig 1: Removing Converter Housing Inspection Cover (8.1L)

   Courtesy of GENERAL MOTORS CORP.
5. Repeat this procedure until you obtain the best possible balance.
   • Unless already removed, remove the starter motor bolts and position the starter motor aside. Refer to Starter Motor Replacement (8.1L Engine) .
   • Remove the torque converter bolts.
     Fig 2: Removing Torque Converter Bolts (8.1L)

     Courtesy of GENERAL MOTORS CORP.
   • Rotate the torque converter one bolt position.
   NOTE: Refer to FASTENER NOTICE .
   • Install the torque converter bolts.

     Tighten:  Tighten the bolts to 60 N.m (44 lb ft).

   • Install the starter motor and starter motor bolts. Refer to Starter Motor Replacement (8.1L Engine) .
   CAUTION: Refer to BATTERY DISCONNECT CAUTION .
   • Connect the battery.
   • Start the vehicle and test for vibration again.
CAUTION: Refer to BATTERY DISCONNECT CAUTION .
6. Disconnect the battery.
7. Raise the vehicle. Refer to Lifting and Jacking the Vehicle .
8. Remove the starter motor bolts and position the starter motor aside. Refer to Starter Motor Replacement (8.1L Engine) .
9. Install the converter housing inspection cover.
10. Install the starter motor and starter motor bolts. Refer to Starter Motor Replacement (8.1L Engine) .
11. Lower the vehicle.
CAUTION: Refer to BATTERY DISCONNECT CAUTION .
12. Connect the battery.