Chevrolet Silverado / GMC Sierra. Service manual — part 60

Fig. 176: Locating Cylinder Head Bolts (Left)
Courtesy of GENERAL MOTORS CORP.

5. Apply sealant to the threads of the NEW cylinder head bolts. Refer to Sealers, Adhesives,

and Lubricants for the correct part number.

6. Install the cylinder head bolts finger tight.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 177: Cylinder Head Bolt Tightening Sequence
Courtesy of GENERAL MOTORS CORP.

7. Tighten the cylinder head bolts using the sequence shown.

Tighten:

1. Tighten the bolts a first pass to 30 N.m (22 lb ft).

2. Tighten the long bolts (1, 4, 5, 8, 9) a final pass to 75 degrees using J 45059 . See

Special Tools.

3. Tighten the medium bolts (12, 13) a final pass to 65 degrees using J 45059 . See

Special Tools.

4. Tighten the short bolts (2, 3, 6, 7, 10, 11) a final pass to 55 degrees using J 45059 .

See Special Tools.

NOTE:

Refer to Fastener Notice .

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 178: Locating Spark Plug Wire Support
Courtesy of GENERAL MOTORS CORP.

8. Install the spark plug wire support and bolts.

Tighten: Tighten the bolts to 12 N.m (106 lb in).

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 179: View Of Spark Plugs (Left)
Courtesy of GENERAL MOTORS CORP.

9. Install the spark plugs.

10. If installing NEW spark plugs measure for the correct gap. Adjust the spark plug gap if

necessary.

Specification: Spark plug gap to 1.52 mm (0.060 in).

Tighten:

Tighten the plugs in a USED cylinder head to 15 N.m (11 lb ft).

Tighten the plugs on the initial installation of a NEW cylinder head to 30 N.m (22 lb
ft).

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado