Chevrolet Silverado / GMC Sierra. Service manual — part 2148

Fig. 116: Valve Lifter Oil Manifold
Courtesy of GENERAL MOTORS CORP.

IMPORTANT:

Do not allow dirt or debris to enter the oil passages of
the manifold. Plug, as required.

Do not disassemble the electrical components from the
manifold.

Do not submerge the electrical components in cleaning
solvent.

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

1. Do not lift the manifold assembly by the electrical lead frame.

Fig. 117: View Of Oil Pressure Sensor, Washer And Valve Lifter Oil Filter
Courtesy of GENERAL MOTORS CORP.

2. Remove the oil pressure sensor (706) and washer (707).

3. Remove the oil screen (452) with O-ring (454).

Do not use the manifold exterior gasket again. Remove
the exterior gasket and install a NEW service gasket
during assembly.

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

4. Clean the manifold with compressed air.

Fig. 118: Electrical Solenoids
Courtesy of GENERAL MOTORS CORP.

5. Inspect for loose electrical solenoids (1-4) or loose or missing bolts.

6. Inspect for damage to the electrical lead frame (5).

7. Inspect for a damaged electrical connector, for bent or corroded pins.

CAUTION: Refer to Safety Glasses and Compressed Air Caution .

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. 119: Sealing Gaskets
Courtesy of GENERAL MOTORS CORP.

8. Inspect for damaged interior sealing gaskets (1-8). If the interior sealing gaskets are

damaged, the manifold must be replaced as an assembly.

9. Inspect for a damaged exterior sealing gasket (9) or scored gasket surfaces.

10. Inspect for debris or restrictions within the oil passages of the manifold. Refer to Cylinder

Deactivation (Active Fuel Management) Valve Lifter Oil Manifold Diagnosis and
Testing .

VALVE ROCKER ARM COVER CLEANING AND INSPECTION

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