GM Service Manual Online
For 1990-2009 cars only

Excessive oil consumption (not due to leaks) is the use of 1.9 L (2 qts) or more of engine oil within 3,200 kilometers (2,000 miles).

The causes of excessive oil consumption includes the following conditions:

    • External oil leaks
        Refer to Oil Leak Diagnosis .
    • Incorrect oil level or improper reading of the oil level indicator. With the vehicle on a level surface, allow adequate drain down time (2-3 minutes) and check for the correct engine oil level.
    • Improper oil viscosity
        Refer to the vehicle owners manual and use the recommended SAE grade and viscosity for the prevailing temperatures.
    • Continuous high speed driving and/or severe usage
    • Crankcase ventilation system restrictions or malfunctioning components
    • Worn valve guides and/or valve stems
        Refer to Cylinder Head Cleaning and Inspection .
    • Worn or improperly installed valve stem oil seals
    • Piston rings broken, worn, or not seated properly. Allow adequate time for the rings to seat.
        Replace broken or worn piston rings as necessary.
    • Piston and rings improperly installed or miss-fitted to the cylinder bore