The lower rail close-out panel (2) is attached to the lower edge of the cowl on the outboard side of the lower rail. The mid-section of the lower rail is sandwiched between the close-out panel and the floor pan for added vehicle strength and ridigity. When performing a full rail replacement, the close-out panel must be removed and installed, or replaced if necessary. The lower rail service part comes as a sub-assembly, which consists of seven brackets and panels. Instruction sheets are also included. The front bumper brackets (3) are available and serviced separately. Diemarks (4) have been added to the rails to indicate sectioning locations. The mid-rail reinforcement (1) panel must be purchased separately for full rail replacement.

Important: The powertrain and engine cradle must be removed from the vehicle to perform the full rail replacement.

1. Remove all related panels and components, including the strut axle assemblies as necessary.
2. Visually inspect and restore as much of the damage as possible to factory specifications.
3. Remove the following as necessary:

•

Sealers

•	Sound deadeners

•	Anti-corrosion materials

4. Remove the close-out panel to access all factory welds attaching the rail to the vehicle
5. Locate, mark, and drill out all factory welds. Note the number and location of the welds for installation of the service rail and components.
6. Remove the damaged rail.

1. Prepare the mating surfaces as necessary.
2. Position the service rail sub-assembly on the vehicle (4).
3. Check the fit with three-dimensional measuring equipment.
4. Position the lower rail close-out panel (2) on the outboard side of the lower rail.
5. Position the mid-rail reinforcement to the new service rail (1).
6. Plug the weld as necessary as noted from the original rail.
7. Position the front bumper mounting brackets (3).
8. Plug the weld accordingly.

Important: 2 of the bumper mounting holes are provided. The 3rd hole is to be located with 3-dimensional measuring equipment.

9. Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM 4901MD-99 Refinish Manual for recommended products. Do not combine paint systems. Refer to paint manufacturers recommendations.

10. Prime with two-part catalyzed primer.
11. Apply the following as necessary:

•

Sealers

•	Anti-corrosion materials

•	Sound deadening materials

12. Install all related panels and components.