Chevrolet Silverado / GMC Sierra. Service manual — part 2157

Fig. 148: Drilling Cylinder Head Bolt Hole
Courtesy of GENERAL MOTORS CORP.

7. Drill out the threads of the damaged hole.

Drill the hole until the stop collar of the drill bit or the sleeve contacts the bushing.

8. Using compressed air, clean out any chips.

IMPORTANT: During the reaming process, it is necessary to repeatedly

remove the drill and clean the chips from the hole.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Fig. 149: Tapping Threads Of Drilled Hole Using Tapping Wrench
Courtesy of GENERAL MOTORS CORP.

9. Using a tap wrench, tap the threads of the drilled hole.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Fig. 150: View Of Tap Upper & Lower Marks, Fixture Plate & Bushing
Courtesy of GENERAL MOTORS CORP.

10. In order to tap the new threads to the proper depth, rotate the tap into the hole until the

mark (1) on the tap aligns with the top of the drill bushing (3).

11. Remove the fixture plate (2), bushing (3), and bolts.

12. Using compressed air, clean out any chips.

13. Spray cleaner GM P/N 12346139, GM P/N 12377981 (Canadian P/N 10953463), or

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

equivalent, into the hole.

14. Using compressed air, clean any cutting oil and chips out of the hole.

Fig. 151: Lubricating Installer Tool Using Driver Oil
Courtesy of GENERAL MOTORS CORP.

15. Lubricate the threads of the installer tool (2) with the driver oil (1).

IMPORTANT: Do not allow oil or foreign material to contact the OD of the

insert.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado