Before addressing the possible reasons for increased oil consumption, it's important to acknowledge that a certain degree of oil consumption is typical for all engines. What is considered normal or acceptable oil consumption can vary significantly between different engines.

While many vehicle drivers believe that engine oil consumption is directly related to the quality of engine oil, and even regard it as one of the most critical factors, there are numerous other potential causes for increased oil consumption. The following are some possible root causes:

• Engine Design and Tolerances: Variations in engine design and manufacturing tolerances can affect how much oil an engine consumes.
• High Age and Long Mileage: Older engines or those with high mileage may naturally consume more oil due to wear and tear.
• Engine Overheating: Overheating, often caused by an inadequately functioning cooling system, can increase oil consumption.
• Worn or Damaged Bearings: Main bearings, connecting rod bearings, camshaft bearings, and crankshaft journals that are worn or damaged can lead to higher oil consumption.
• Worn or Damaged Piston Rings and Valve Components: Worn piston rings, ring grooves, valve stems, and guides can contribute to increased oil consumption.
• Increased Piston Clearances and Distorted Cylinder Liners: Larger clearances and distortions in cylinder liners can result in higher oil usage.
• Damaged Seals and Gaskets: Faulty seals and gaskets may cause oil leaks and increased consumption.
• Leaking Turbocharger Seal: A damaged turbocharger seal can lead to oil leakage and consumption.
• Clogged PCV Valve: A clogged Positive Crankcase Ventilation (PCV) valve can affect oil consumption.
• Fuel Dilution: Fuel mixing with engine oil can increase oil consumption.
• Oil Pressure Too High: Excessive oil pressure can lead to increased consumption.
• Excess Engine Oil in Crankcase: Too much oil in the crankcase can cause higher consumption.
• Inappropriate SAE Engine Oil Viscosity: Using oil with the wrong viscosity rating can impact oil consumption.
• Selection of Low Quality or Incorrect Engine Oil: Poor-quality or incorrect engine oil can affect consumption and overall engine performance.

Identifying and addressing these factors can help manage and potentially reduce engine oil consumption.