Energy Conserving Oils. Oils marketed as "Energy Conserving" are intended to improve fuel economy in
passenger car engines. Some of these oils contain friction modifier chemical additives. One additive,
molybdenum dithioposphate, has been implicated in copper corrosion problems in some heavy- duty diesel
engines. Therefore, until further information is available, do not use an "Energy Conserving" oil containing
molybdenum dithiophosphate in any IH built engine. In addition, some "Energy Conserving" oils meet only API
Category SF for spark ignition engines, and do not meet the oil quality requirements for diesel engines.