Oil Pump: Inspection
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Remove oil pump gear cover bolts. Remove oil pump gear cover. Use a feeler gauge to measure clearance between gear teeth and oil pump housing. The production clearance is 0.0049-0.0087" (0.125-0.221 mm) and service limit is 0.0087" (0.221 mm). Replace oil pump assembly if clearance exceeds service limit.
- Use a feeler gauge and a straightedge to measure clearance between the side of the gear and the cover. The production clearance is 0.0025-0.0043" (0.064-0.109 mm) and service limit is 0.0043" (0.109 mm). Replace oil pump assembly if clearance exceeds service limit.
- Calculate driven gear shaft to bushing clearance. Measure driven gear shaft outside diameter. The production specification is 0.7853-0.7858" (19.947-19.960 mm) and service limit is 0.7819" (19.86 mm). Measure driven gear bushing inside diameter. The production value is 0.7874" (20 mm). Calculate driven gear shaft to bushing clearance. The service limit is 0.0055" (0.14 mm).
- Replace oil pump assembly if clearance exceeds service limit. Install oil pump gear cover to oil pump assembly. Install oil pump gear cover bolts.