GM Service Manual Online
For 1990-2009 cars only

Transmission Support Crossmember Replacement 2WD

Removal Procedure

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Support the transmission with a suitable stand or jack.

  3. Object Number: 647997  Size: SH
  4. Remove the nuts retaining the transmission mount to the transmission support. Refer to Transmission Mount Replacement for the 4L60E/4L65E transmission or Transmission Mount Replacement for the Aisin AR5 transmission.
  5. Raise the transmission.

  6. Object Number: 1241432  Size: SH
  7. Remove the vertical bolts retaining the transmission support to the frame.

  8. Object Number: 1241428  Size: SH
  9. Remove the horizontal nuts and the bolts retaining the transmission support to the frame.
  10. Remove the transmission support from the frame.

Installation Procedure


    Object Number: 1241428  Size: SH
  1. Install the transmission support to the frame.
  2. Loose install the horizontal nuts and the bolts retaining the transmission support to the frame.
  3. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1241432  Size: SH
  4. Loose install the vertical bolts retaining the transmission support to the frame.
  5. • Tighten the horizontal nuts to 50 N·m (37 lb ft).
    • Tighten the vertical bolts to 100 N·m (74 lb ft).
  6. Lower the transmission.

  7. Object Number: 647997  Size: SH
  8. Install the nuts to the transmission mount. Refer to Transmission Mount Replacement for the 4L60E/4L65E transmission or Transmission Mount Replacement for the Aisin AR5 transmission.
  9. Remove the stand or jack.
  10. Lower the vehicle.

Transmission Support Crossmember Replacement 4WD

Removal Procedure

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Support the transmission with a suitable stand or jack.
  3. Raise the transmission.

  4. Object Number: 647997  Size: SH
  5. Remove the nuts retaining the transmission mount to the transmission support. Refer to Transmission Mount Replacement in Automatic Transmission - 4L60-E/4L65-E or Transmission Mount Replacement in Manual Transmission - Aisin AR5.

  6. Object Number: 1241426  Size: SH
  7. Remove the vertical bolts retaining the transmission support to the frame.

  8. Object Number: 1241425  Size: SH
  9. Remove the horizontal nuts and the bolts retaining the transmission support to the frame.
  10. Remove the transmission support from the frame.

Installation Procedure


    Object Number: 1241425  Size: SH
  1. Install the transmission support to the frame.
  2. Loosely install the horizontal nuts and the bolts retaining the transmission support to the frame.
  3. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1241426  Size: SH
  4. Loosely install the vertical bolts retaining the transmission support to the frame.
  5. • Tighten the horizontal nuts to 50 N·m (37 lb ft).
    • Tighten the vertical bolts to 100 N·m (74 lb ft).
  6. Lower the transmission.

  7. Object Number: 647997  Size: SH
  8. Install the nuts to the transmission mount. Refer to Transmission Mount Replacement in Automatic Transmission - 4L60-E/4L65-E or Transmission Mount Replacement in Manual Transmission - Aisin AR5.
  9. Remove the stand or jack.
  10. Lower the vehicle.