General Motors — Oil Pump Inspection
Testing & diagnosis
From a General Motors service manual — check it applies to your exact model before use.
Procedure
- Inspect pump body and cover for cracks or excessive wear. Inspect pump gears for damage or wear.
- Check drive gear shaft for looseness in pump body. Check pressure regulator valve for fit in bore. Replace entire pump assembly if damaged.
- Inspect inlet tube and screen assembly for damage.
Source: General Motors service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.