System and method for determining oil change interval

A method for determining the remaining life of engine oil in an engine, comprising:

• measuring a plurality of engine parameters including engine speed, fueling rate, engine load, and engine temperature using a plurality of engine sensors arranged on the engine;
• periodically calculating an estimated value of soot generated for a time period between periodic calculations based on the measured engine parameters using an electronic controller;
• accumulating the estimated values of soot;
• periodically calculating an estimated depletion of total base number for a time period between periodic calculations based on the measured engine parameters;
• accumulating the estimated depletions of total base number;
• periodically calculating an increase in oil viscosity a time period between periodic calculations based on the measured engine parameters;
• accumulating the estimated increases in oil viscosity;
• correlating the accumulations of the estimated values of soot, of the estimated depletions of total base number, and of the estimated increases viscosity to an oil life value representing the remaining life of engine oil;
• providing an indication when the oil life value reaches a predetermined magnitude.

A oil indicator system for determining the remaining life of engine oil in an engine based upon at least one oil property including soot concentration, viscosity increase and total base number depletion, the system comprising:

• a plurality of engine sensors arranged on the engine for sensing a plurality of engine parameters;
• an electronic controller in electrical communication with the engine sensors, the electronic controller periodically calculating an estimated soot concentration, viscosity increase and total base number depletion of the oil, based on the sensed engine parameters;
• means for respectively accumulating the estimated soot concentration, viscosity increase and total base number depletion;
• and
• means for indicating when the respective accumulation of any of the estimated soot concentration, viscosity increase or total base number depletion reaches a respective predetermined magnitude.

A method for determining the remaining life of engine oil in an engine, the engine oil having an oil life being determined by degradation of at least one oil property, wherein the degradation of at least one oil property includes a total base number depletion, the method comprising:

• measuring a plurality of engine parameters;
• periodically calculating an estimated total base number depletion based on the plurality of engine parameters;
• accumulating the estimated total base number depletion;
• and
• providing an indication when the accumulation of the estimated total base number depletion reaches a predetermined magnitude.

An oil indicator system for determining the remaining life of engine oil in an engine according to at least one oil property, the at least one property including an increase of viscosity in the oil, the system comprising:

• a plurality of engine sensors arranged on the engine for sensing a plurality of engine parameters;
• an electronic controller in electrical communication with the engine sensors, the electronic controller periodically calculating an estimated viscosity increase based on the sensed engine parameters;
• means for accumulating the estimated viscosity increase;
• and
• means for indicating when the accumulation of the estimated viscosity increase reaches a predetermined magnitude.

An oil indicator system for determining the remaining life of engine oil in an engine according to at least one oil property, the at least one property including a total base number depletion, the system comprising:

• a plurality of engine sensors arranged on the engine for sensing a plurality of engine parameters;
• an electronic controller in electrical communication with the engine sensors, the electronic controller periodically calculating an estimated total base number depletion based on the sensed engine parameters;
• means for accumulating the estimated total base number depletion;
• and
• means for indicating when the accumulation of the estimated total base number depletion reaches a predetermined magnitude.