GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

J 42058 Frame Adapter Clamp

    Important: To increase accessibility to the front impact bar, rotate the front brake ducts and manually raise the headlamps.

  1. Remove the following panels and components to gain access to the impact bar:
  2. • The bumper cover
    • The impact absorbers
    • The fog lamps

    Notice: Be sure to protect vehicle components before cutting or grinding on the bumper impact bar or frame rails.

  3. Visually inspect and restore as much of the damage as possible to specifications using three-dimensional measuring procedures. Use J 42058 to secure the vehicle if pulling and straightening are required.
  4. Remove or reposition wiring to avoid damage.

  5. Object Number: 181151  Size: SH
  6. Cut the welds around the perimeter of the frame rail (fishmouth) ends. Cut welds favoring the impact bar side of the joint. Do not cut into the frame rails.
  7. Remove the damaged impact bar.

  8. Object Number: 181153  Size: SH
  9. Extract pieces of the impact bar left attached to the rail ends. Keep the perimeter and shape of the rail end (fishmouth) as original as possible.

Installation Procedure

  1. Straighten and deburr the rail ends to allow the service impact bar to fit properly.
  2. Temporarily position the impact bar and scribe lines into the primer indicating where the welds will be made.
  3. Remove the primer from the areas to be MIG welded by sanding with 80-grit paper on a Dual-Action (DA) sander. Do not use a grinder to remove the primer.
  4. Prepare all bare metal surfaces and apply weld-through primer as necessary. Be sure to apply primer to the inside of the 'fishmouth' area also.
  5. Position the bumper impact bar using three-dimensional measuring equipment and install per the original weld locations.

  6. Object Number: 181151  Size: SH
  7. Stitch weld around the 'fishmouth' joint.
  8. • If no trace of the original welds are present, follow the pattern specified for welding the side rails to the impact bar. This weld pattern will create a solid weld joint with minimal heat distortion.
    • Clean and prepare all welded surfaces, use 3Ms Scotch-Brite® Clean-N-Strip Discs (disc P/N 07460, mandrel P/N 07491) or equivalent.
  9. Prime with two-part catalyzed primer.
  10. Apply anti-corrosion materials to all inner surfaces as necessary. Do not combine paint systems. Refer to paint manufacturer's recommendations.
  11. Install the following panels and components.
  12. • The bumper cover
    • The impact absorbers
    • The fog lamps