Removal Procedure
- Remove all related panels and components.
- Visually inspect and restore as much of the damage as possible to factory specifications.
- Remove the following as necessary:
- Locate, mark and drill out all factory welds. Note the number of welds for installation of the service assembly.
- Remove the damaged front upper rail assembly.
Important: The left and right front upper rails are serviced as assemblies. The upper rails should be replaced at factory seams.
| • | Sealers |
| • | Sound deadeners |
| • | Anti-corrosion materials |
Installation Procedure
- Prepare mating surfaces.
- Drill 8 mm (5/16 in) plug weld holes on the service part as noted from the original assembly.
- Position the service assembly.
- Check fit of body dimensions. Use three-dimensional measuring equipment.
- Plug weld accordingly.
- Clean and prepare welded surfaces.
- Prime with two-part catalyzed primer.
- Apply sealers and anti-corrosion materials as necessary.
Caution: Foam sound deadeners must be removed from areas within 152.4 mm (6 in) of where flame is to be used for body repairs. When reinstalling foam sound deadeners, avoid inhaling fumes as bodily injury may result.
Important: There are a number of welds attaching the rear of the upper rail to the cowl panel. These welds can be accessed through the openings on the outboard side of the upper rail (1). Do not drill through the cowl panel when removing these welds.
When repairing an existing upper rail the hood hinge mounting locations must be inspected for stress or metal fatigue (2). Torque the hood hinge mounting bolts to 12 N·m (106 lbs in). The upper rail must be replaced if any damage to the hood hinge mounting locations is evident.Important: Prior to refinishing, refer to GM 4901MD-99 Refinish Manual for recommended products. Do not combine paint systems. Refer to paint manufacturer's recommendations.
