1
Kevin R Carlstrom, Gerald L Larson, Frank Bondarowicz: Method of estimating engine lubricant condition. International Truck Intellectual Property Company, Jeffrey P Calfa, Dennis Kelly Sullivan, Susan L Lukasik, July 26, 2005: US06920779 (35 worldwide citation)

A motor vehicle having an internal combustion engine and a lubricating oil circulation system provides estimates of the distance remaining before an oil change becomes imperative. An indirect estimate of the depletion of various additives and the deterioration of oil operating characteristics is bas ...


2
Kevin R Carlstrom, Gerald L Larson, Frank Bondarowicz: Method of estimating engine lubricant condition. International Truck Intellectual Property Company, May 20, 2004: US20040093931-A1

A motor vehicle having an internal combustion engine and a lubricating oil circulation system provides estimates of the distance remaining before an oil change becomes imperative. An indirect estimate of the depletion of various additives and the deterioration of oil operating characteristics is bas ...