GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Important: The following service procedures (steps 1 and 2) are for the removal and or replacement of the support brace from the cradle.

    Important: In steps 2-9, use a transmission jack or the help of an assistant to remove the support brace, floor tunnel brace, and the rear crossmember brace from the vehicle.

  1. Install the engine support fixture. Refer to Engine Support Fixture .

  2. Object Number: 1820375  Size: SH
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  4. Remove the support brace mounting bolts (1), for vehicles equipped with the 3.5L (LZ4) or 3.9L (LZ9) engines.
  5. Remove the support brace (2), for vehicles equipped with the 3.5L (LZ4) or 3.9L (LZ9) engines.

  6. Object Number: 1820362  Size: SH
  7. Remove the floor tunnel panel brace mounting bolts.

  8. Object Number: 1820372  Size: SH
  9. Remove the mounting bolts for the exhaust shield.
  10. Remove the floor tunnel panel brace.

  11. Object Number: 1820411  Size: SH
  12. Remove the mounting bolts for the rear crossmember brace.
  13. Remove the rear crossmember brace.

Installation Procedure

    Important: In steps 1-8, use a transmission jack or the help of an assistant to install the support brace, floor tunnel brace, and the rear crossmember brace in the vehicle.


    Object Number: 1820375  Size: SH
  1. Position the support brace (2) on the cradle, for vehicles equipped with the 3.5L (LZ4) or 3.9L (LZ9) engines.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the support brace bolts (1).
  4. Tighten
    Tighten the bolts to 100 N·m (73 lb ft) plus 180 degrees rotation.


    Object Number: 1820372  Size: SH
  5. Position the floor tunnel panel brace on the vehicle.
  6. Hand tighten the mounting bolts.
  7. Important: Tighten all the tunnel panel mounting bolts at the same time.

  8. Install the tunnel panel brace mounting bolts.
  9. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).


    Object Number: 1820362  Size: SH
  10. Install the remaining tunnel panel mounting bolts.
  11. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).


    Object Number: 1820411  Size: SH
  12. Position the rear crossmember brace on the vehicle.
  13. Install the crossmember brace mounting bolts.
  14. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).

  15. Lower the vehicle.
  16. Remove the engine support fixture. Refer to Engine Support Fixture .