The strut cap is attached to the lower plenum. The lower plenum is formed from laminated steel. This steel is constructed by bonding 2 pieces of cold rolled steel (1) with a viscoelastic layer of adhesive (2). MIG welding laminated steel does not meet GM corporate standards for structural integrity. Therefore, do not try to MIG weld the strut cap to the laminated lower plenum.

The front wheelhouse may be serviced in one of two ways. If the laminated steel lower plenum is damaged beyond repair and needs to be replaced, then the complete wheelhouse assembly with the upper strut cap attached may be installed (1). Refer to Front Wheelhouse Replacement . However, if the wheelhouse assembly is damaged below the strut cap, then leave the strut cap welded to the lower plenum and remove only the wheelhouse skirt (2).

Caution: Refer to Approved Equipment for Collision Repair Caution in the Preface section.




1. Disable the SIR system. Refer to SIR Disabling and Enabling .
2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
3. Remove all related panels and components.
4. Repair as much of the damage as possible to factory specifications. Refer to Dimensions - Body .
5. Note the location and remove the sealers and anti-corrosion materials from the repair area, as necessary. Refer to Anti-Corrosion Treatment and Repair .




Important: Do not remove the strut cap from the vehicle. Drill out all other welds but leave the strut cap welded to the lower plenum. Do not damage any inner panels or reinforcements.

6. Locate and drill out all factory welds.

Important: Note the number and location of welds for installation of the front wheelhouse




7. Remove the damaged wheelhouse assembly from the vehicle.

Important: If the location of the original plug weld holes can not be determined, space the plug weld holes every 40 mm (1 ½ in) apart.

Some panels may have structural weld-thru adhesive. It is necessary to replace the weld-thru adhesive with an additional spot weld between each factory spot weld.
1. Locate and drill out the factory welds to separate the strut cap from the wheelhouse assembly.
2. Drill 8 mm (5/16 in) plug weld holes in the service part as necessary in the locations noted from the original assembly.



3. Remove and discard the strut cap from the wheelhouse assembly.
4. Prepare the mating surfaces as necessary.
5. Apply GM-approved Weld-Thru Coating or equivalent to all mating surfaces. Refer to Anti-Corrosion Treatment and Repair .



6. Position the front wheelhouse to the vehicle using 3-dimensional measuring equipment. Clamp the wheelhouse in place.



7. Plug weld accordingly.
8. Clean and prepare all of the welded surfaces.
9. Apply the sealers and anti-corrosion materials to the repair area, as necessary. Refer to Anti-Corrosion Treatment and Repair .
10. Paint the repaired area. Refer to Basecoat/Clearcoat Paint Systems .
11. Install all related panels and components.
12. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
13. Enable the SIR system. Refer to SIR Disabling and Enabling .