Chevrolet Silverado / GMC Sierra. Service manual — part 200

Press the oil pan gasket into the grooves of the engine front cover and crankshaft rear oil
seal housing.

5. Slide the oil pan back against a suitable straight edge.

Fig. 668: Measuring Pan-To-Transmission Housing Clearance
Courtesy of GENERAL MOTORS CORP.

6. Install the oil pan bolts and nuts, but do not tighten.

7. Measure the pan-to-transmission housing clearance using a feeler gage and a straight edge.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Use a feeler gage to check the clearance between the oil pan-to-transmission housing
measurement points. If the clearance exceeds 0.3 mm (0.011 in) at any of the 3 oil pan-to-
transmission housing measurement points (1), then repeat the step until the oil pan-to-
transmission housing clearance is within the specification. The oil pan must always be
forward of the rear face of the engine block.

Fig. 669: Oil Pan Bolts & Nuts Tightening Sequence
Courtesy of GENERAL MOTORS CORP.

NOTE:

The alignment of the mating components is crucial. An offset
greater than 0.30 mm (0.011 in) between the rear faces of the

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

8. Tighten the oil pan bolts and nuts in sequence (1-12).

Tighten: Tighten the oil pan bolts to 25 N.m (18 lb ft).

9. Measure the clearance between the 3 oil pan-to-transmission housing measurement points in

order to ensure proper alignment.

oil pan and block is not acceptable. Offsets greater than 0.30
mm (0.011 in) will affect the alignment between the engine
assembly and the transmission. Mis-alignment of the engine
assembly to the transmission can lead to internal and external
damage to the engine assembly and/or transmission.

NOTE:

Refer to Fastener Notice .

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 670: Identifying Oil Drain Plug
Courtesy of GENERAL MOTORS CORP.

10. Install a NEW oil pan drain plug seal, O-ring, onto the oil pan drain plug.

11. Install the oil pan drain plug into the oil pan.

Tighten: Tighten the oil pan drain plug to 25 N.m (18 lb ft).

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado