Chevrolet Silverado / GMC Sierra. Service manual — part 572

Fig. 174: Measuring Camshaft Lobe Lift
Courtesy of GENERAL MOTORS CORP.

4. Measure the camshaft lobe lift. The production value for intake is 7.273 mm (0.2863 in).

5. The production value for exhaust is 5.907 mm (0.2326 in).

6. Replace the camshaft if the measured value is less than the service limit.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 6.6L - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 175: Measuring Camshaft Runout
Courtesy of GENERAL MOTORS CORP.

7. Measure the camshaft runout.

Mount the camshaft on the V-blocks.

Use J 7872 to measure the camshaft runout.

The runout service limit is 0.05 mm (0.0020 in).

8. Replace the camshaft if the run-out is over the service limit.

CRANKSHAFT AND BEARING CLEANING AND INSPECTION

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 6.6L - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Special Tools

J 7872 Dial Indicator Set

J 45059 Angle Meter

Inspection

Fig. 176: Measuring Crankshaft Run Out
Courtesy of GENERAL MOTORS CORP.

1. Clean the crankshaft and bearings.

2. Inspect the crankshaft for the following conditions.

Excessive wear or damage on the surface of the crankshaft journals.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 6.6L - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Excessive wear or damage to the crankshaft gear.

Excessive wear or damage on the oil seal fitting surface.

Inspect the oil ports for obstructions.

Replace the crankshaft if there is excessive wear or damage to the journals, oil seal
fitting surface or to the crankshaft gear.

3. Measure the crankshaft run out.

Mount the crankshaft in wooden V-blocks.

Set J 7872 on the center of the crankshaft journal.

Turn the crankshaft in the normal direction of rotation.

Record readings. The production value is 0.05 mm (0.0020 in) and the service limit is
0.44 mm (0.0173 in).

Fig. 177: Measuring Crankshaft Journal Diameter
Courtesy of GENERAL MOTORS CORP.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 6.6L - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado