Patent ID: 8021558

Claim:
A method for dispersing an oil additive into an oil passing through a filter of an engine, the method comprising: filling a first cavity of an additive cartridge with an oil viscosity modifier configured to reduce a viscosity of the oil, the first cavity being adjacent to and separated from a second cavity of the additive cartridge; locating the first cavity and at least a portion of the second cavity of the additive cartridge within a filter element disposed within a housing of the filter, the first cavity and the second cavity of the additive cartridge being centrally located within an inner area defined and surrounded by the filter element and within a flow path through the filter, the second cavity being separated from the first cavity by a dividing wall and the second cavity does not have any additive disposed therein, the second cavity defining a first fluid path through the additive cartridge and the oil must pass through the second cavity in order to exit the filter, wherein the first cavity is completely received within the filter element and at least a portion of the second cavity is also received within the filter element; and metering the additive through an opening in the additive cartridge, the opening providing a second fluid path only in fluid communication with the first cavity of the additive cartridge.