GM Service Manual Online
For 1990-2009 cars only

Service Part Preparation Procedure


Object Number: 1548251  Size: SH

Important: The wheel opening flange should bend upwards. Do not repair this normal condition. Take note of the shape of the flange for installation purposes. Do not flatten the flange.

Important: When damage to the rest of the panel is minimal, repair the outer rear wheelhouse by sectioning.

Before you remove the damaged section of the panel from the vehicle, prepare the service assembly in order to become familiar with the procedure, to know exactly where to cut the damaged panel for a better fit of the new section.


    Object Number: 1548246  Size: SH
  1. Apply a strip of masking tape (a) that is 20 mm (¾ in) along the vertical surface of the wheelhouse radius to form a welding flange.

  2. Object Number: 1548248  Size: SH
  3. On the service part, cut along the inner edge of the tape location.

  4. Object Number: 1548249  Size: SH
  5. Remove the excess portion of the wheelhouse.

Removal Procedure

  1. Remove all the related panels and the components.
  2. Visually inspect the damage.
  3. Remove the following components as necessary:
  4. • The sealers
    • The sound deadeners
    • The anti-corrosion materials

    Object Number: 1548246  Size: SH
  5. Apply a strip of 20-mm (¾-in) masking tape along the horizontal surface of the wheelhouse radius.
  6. On the vehicle, cut along the outboard side of the masking tape (a) in order to create a tab for the weld flange on the new wheelhouse section.
  7. Remove the damaged section of the wheelhouse.

Installation Procedure


    Object Number: 1548251  Size: SH
  1. Mark the plug weld holes every 40 mm (1½ in) along the weld flange on the service part.
  2. Position the service part.
  3. Temporarily align the sheet metal screw to the quarter inner portion of the inner body side panel.
  4. Install the quarter panel outer. Position the panel to the vehicle, using 3-dimensional measuring equipment. Clamp the panel in place.
  5. Verify the fit of the panels. Adjust the panels as necessary. Temporarily sheet metal screw the panel in place (a).
  6. Remove the quarter outer panel.
  7. Remove the service part.
  8. Drill 8 mm (5/16 in) along the weld flange on the service part.
  9. Prepare the mating surfaces for welding, as necessary.
  10. Apply GM-approved weld-thru Coating or equivalent to all mating surfaces. Refer to Anti-Corrosion Treatment and Repair .
  11. Install the service wheelhouse outer panel in the proper position, as verified in the previous steps.
  12. Plug weld accordingly the wheelhouse outer to the vehicle.
  13. Apply sound deadening materials as necessary.
  14. Apply the sealers and anti-corrosion materials to the repair area, as necessary. Refer to Anti-Corrosion Treatment and Repair .
  15. Paint the repair area. Refer to Basecoat/Clearcoat Paint Systems .
  16. Install all related panels and components.
  17. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  18. Enable the SIR system. Refer to SIR Disabling and Enabling .