GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Century (China) (CNG) 🢒 Body and Accessories 🢒 Seats 🢒 Seat Adjuster Phase Adjustment - Manual

Removal Procedure
  1. Remove the front seat from the vehicle. Refer to Front Seat Replacement - Bucket .

    2. Object Number: 310454 Size: SH
  2. Place the seat upside down on a clean, protected surface.

    3. Do not leave the seat upside down on the cushion.

  3. Remove the finish panels. Refer to Front Seat Trim Panel Replacement .
  4. Remove the seat cushion cover. Refer to Front Seat Cushion Cover Replacement .
  5. Remove the seat cushion pad.
  6. Remove the adjuster to seat cushion frame bolts.
  7. Remove the adjuster from the seat cushion frame.
  8. Remove the adjuster crosswire and assist springs.
  9. Remove the crossbrace in order to separate the left and the right adjusters.

Installation Procedure

    Object Number: 310454 Size: SH
  1. Attach a crossbrace to the left and the right adjusters.
  2. Ensure that the tab bending downward at the center of the crossbrace faces the rear of the adjusters.

    3. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Secure the crossbrace with 2 bolts.

    4. Tighten
    Tighten the crossbrace bolts to 6 N·m (53 lb in).

  4. Install the adjuster crosswire and assist springs.

    5. Important: Install the right and left seat adjuster sliding mechanism in the same position that the mechanism had when you attached the adjuster-to-seat bottom frame.

    Install the adjuster assembly to the floorpan attachments before you attach the adjusters to the seat. Use the floorpan as a guide during assembly in order to ensure correct adjuster alignment. The floorpan will act as an assembly fixture.

  5. Install the adjuster assembly to the floorpan.
  6. Install the seat adjuster to floorpan bolts.

    7. Tighten
    Tighten the adjuster to floorpan bolts to 42 N·m (31 lb ft).

  7. Install the seat to the adjuster assembly.
  8. Install the adjuster to the seat cushion frame bolts.

    9. Tighten
    Tighten the adjuster to the seat cushion frame bolts to 24 N·m (18 lb ft).

  9. Install the seat cushion pad.
  10. Install the seat cushion cover. Refer to Front Seat Cushion Cover Replacement .
  11. Install the finish panels. Refer to Front Seat Trim Panel Replacement .
  12. Connect the electrical connectors, if equipped.
  13. Install the front seat in the vehicle. Refer to Front Seat Replacement - Bucket .
  14. Inspect the operation of the manual seat adjusters.