Clean- A lubricant must maintain internal cleanliness by suspending contaminants from adhering to components.

Cool Moving Elements- Reducing friction will reduce the amount of heat that is generated and lower the operating temperature of the components. A lubricant must also absorb heat from components and transfer it to a location where it can be safely dissipated.

Prevent Contamination- The lubricant should act as a dynamic seal in locations such as the pistons, piston rings and cylinder contact areas. This minimizes contamination by combustion by-products (for example) in the lubricating system. Lubricants are also relied upon to support mechanical seals found elsewhere and to minimize external contamination and fluid loss.

Dampen Shock- The lubricant may be required to cushion the blows of mechanical shock. A lubricant film can absorb and dispense energy spikes over a broader contact area.

Transfer Energy- A lubricant may be required to act as an energy transfer median as in the case of hydraulic equipment or lifters in an automotive engine.

Prevention Corrosion- A lubricant must also have the ability to prevent or minimize internal component corrosion. This can be accomplished either by chemically neutralizing the corrosive products or by setting up a barrier between the components and the corrosive material.