Method for preventing or reducing low speed pre-ignition

Abstract

A method for preventing or reducing low speed pre-ignition in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and at least one lubricating oil additive, as a minor component. The lubricating oil contains at least one metal or metalloid in an amount sufficient that, in thermogravimetric measurements of the lubricating oil by a Thermogravimetric Engine Oil Simulation Test, carbon black decomposition temperature is increased as compared to the carbon black decomposition temperature in a lubricating oil containing calcium or magnesium. A lubricating oil useful for preventing or reducing low speed pre-ignition in an engine lubricated with the lubricating oil. The lubricating oils of this disclosure are particularly advantageous as passenger vehicle engine oil (PVEO) products.

Dependencies are inferred from the claim text.