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(Abbreviation)
The Total Base Number (TBN), as defined by ASTM D2896, is a measure of the alkaline reserve in a lubricant. It represents the amount of acid that can be neutralized by a given quantity of oil. TBN is typically measured in milligrams of potassium hydroxide (KOH) per gram of oil.

In the context of motor oil, TBN is an important property because it indicates the oil’s ability to neutralize acids formed during the combustion process in an engine. As oil circulates through the engine, it comes into contact with acidic by-products of combustion, such as sulfuric acid. If left unchecked, these acids can lead to corrosive wear and damage to engine components.

By maintaining a sufficient TBN level, motor oil can effectively neutralize these acids, preventing them from causing harm to the engine. Monitoring TBN levels helps determine the oil’s remaining alkaline reserve and informs decisions regarding oil change intervals and maintenance schedules.

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