Chevrolet Silverado / GMC Sierra. Service manual — part 2120

1. Clean the varnish and carbon from the piston (107) using cleaning solvent.

2. Dry the components with compressed air.

CAUTION: Refer to Safety Glasses 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. 30: Cleaning Piston Ring Grooves With Suitable Ring Groove Cleaning Tool
Courtesy of GENERAL MOTORS CORP.

3. Clean the piston ring grooves with a suitable ring groove cleaning tool.

4. Clean the oil lubrication holes and slots.

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. 31: Identifying Piston Damage Inspection Areas
Courtesy of GENERAL MOTORS CORP.

5. Inspect the piston for the following conditions:

Cracks in the piston ring lands, the piston skirt, or pin bosses

Piston ring grooves for nicks, burrs, or warpage which may cause the piston ring to
bind

MINOR imperfections may be removed from the piston with a fine file.

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

Eroded areas at the top of the piston (1)

Scuffed or damaged skirts (2)

Scoring to the piston pin bore (3) or piston pin

Fig. 32: Inserting Piston Ring Into Ring Groove
Courtesy of GENERAL MOTORS CORP.

6. Insert the edge of the piston ring into the piston ring groove.

Roll the piston ring completely around the piston. If binding is caused by a distorted ring
groove, MINOR imperfections may be removed with a fine file. If binding is caused by a

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