Chevrolet Silverado / GMC Sierra. Service manual — part 1274

Fig. 19: View Of 50 mm Backing Plate
Courtesy of GENERAL MOTORS CORP.

2. Create a 50 mm (2 in) backing plate from the unused portion of the service part. Trim the backing plate as

necessary to fit behind the sectioning joint.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Collision Repair - - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Fig. 20: Drilling 8 mm Plug Weld Holes
Courtesy of GENERAL MOTORS CORP.

3. Drill 8 mm (5/16 in) plug weld holes along the sectioning cut on the remaining original part. Locate these

holes approximately 25 mm (1 in) (a) from the edge and spaced 40 mm (1 1/2 in) apart.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Collision Repair - - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Fig. 21: Drilling Windshield Frame Pillar Plug Weld Holes
Courtesy of GENERAL MOTORS CORP.

4. Drill 8 mm (5/16 in) plug weld holes in the service part as necessary in the locations noted from the

original panel and along the sectioning cut.

IMPORTANT: If the location of the original plug weld holes can not be determined, or if

structural weld-thru adhesive was present, space the plug weld holes
every 40 mm (1 1/2 in) apart.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Collision Repair - - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Fig. 22: Plug Welding Backing Plate
Courtesy of GENERAL MOTORS CORP.

5. Prepare all attachment surfaces as necessary.

6. Apply GM-approved Weld-Thru Coating or equivalent to all mating surfaces. Refer to Anti-Corrosion

Treatment and Repair .

7. Fit the backing plate (2) halfway into the sectioning joint, clamp and plug weld to the vehicle (3).

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Collision Repair - - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado