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The causes of excessive oil consumption may include the following conditions:
- External oil leaks. 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. Crankcase Ventilation System Inspection/Diagnosis
- Worn valve guides and/or valve stems
- Worn or improperly installed valve stem oil seals. Gas Engine Ignition Spark Plug Inspection
- Piston rings broken, worn, or not seated properly
Allow adequate time for the rings to seat. Cylinder Leakage Test
Replace worn piston rings, as necessary. Piston and Connecting Rod Overhaul
- Piston and rings improperly installed or not fitted to the cylinder bore. Lower Engine Noise, Regardless of Engine Speed
- Scuffed or damaged Piston skirt coating. Piston and Connecting Rod Overhaul
- Excessive Piston to Cylinder wall clearance or excessive Piston taper or out-of-round. Engine Mechanical Specifications (L84)
, or Engine Mechanical Specifications (L87)
- Worn, damaged or improperly installed Valve Stem Guides. Cylinder Head Overhaul
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