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Makes 🢒 GMC_Truck 🢒 2009 🢒 Yukon Denali 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Oil Consumption Diagnosis

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Causes

Excessive oil consumption, not due to leaks, is the use of 1 L (1 qt) or more of engine oil within 3 200 kilometers (2,000 miles).

Preliminary

The causes of excessive oil consumption may include 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, run the engine for a few minutes, allow adequate drain down time, 2-3 minutes, and measure 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
    • Worn or improperly installed valve stem oil seals
        Refer to Spark Plug Inspection .
    • Piston rings broken, worn, or not seated properly
        Allow adequate time for the rings to seat.
        Replace worn piston rings, as necessary.
        Refer to Cylinder Leakage Test .
    • Piston and rings improperly installed or not fitted to the cylinder bore