Chevrolet Silverado / GMC Sierra. Service manual — part 1802

5. Remove the spark plug wires (1) from the spark plugs.

1. Twist the spark plug wire boot a 1/2 turn.

2. Pull only on the boot in order to remove the wire from the spark plug.

6. Remove the spark plug wires from the ignition coils.

1. Twist the spark plug wire boot a 1/2 turn.

2. Pull only on the boot in order to remove the wire from the ignition coil.

Fig. 37: View Of Oil Level Indicator, Tube Bolt, Indicator Tube & O-Ring Seal
Courtesy of GENERAL MOTORS CORP.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Exhaust - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

7. Remove the oil level indicator tube bolt (419).

8. Remove the oil level indicator tube (420) from the engine block.

Fig. 38: View Of Exhaust Manifold, Gasket & Bolts
Courtesy of GENERAL MOTORS CORP.

9. Remove the exhaust manifold bolts and exhaust manifold.

10. Remove and discard the exhaust manifold gasket.

11. Remove and discard the exhaust manifold seal.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Exhaust - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 39: View Of Exhaust Manifold Heat Shield & Bolts
Courtesy of GENERAL MOTORS CORP.

12. If replacing the exhaust manifold, remove the exhaust manifold heat shield bolts, and shield

from the exhaust manifold.

Installation Procedure

IMPORTANT:

Tighten the exhaust manifold bolts as specified in the
service procedure. Improperly installed and/or leaking
exhaust manifold gaskets may affect vehicle emissions
and/or On-Board Diagnostics (OBD) II system performance.

The cylinder head exhaust manifold bolt hole threads must
be clean and free of debris or threadlocking material.

Do not apply sealant to the first 3 threads of the bolt.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Exhaust - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 40: View Of Exhaust Manifold Heat Shield & Bolts
Courtesy of GENERAL MOTORS CORP.

1. If the exhaust manifold was replaced, position and install the exhaust manifold heat shield,

and bolts to the exhaust manifold.

Tighten: Tighten the bolts to 9 N.m (80 lb in).

NOTE:

Refer to Fastener Notice .

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Exhaust - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado