Everlube Reservoris' Oil Reservoirs are designed to store any fluid until it is needed. Generally, the reservoirs are tapped into an engine’s oil pan for the extra quarts desired on hand. These reservoirs have also been used in hydraulic applications. Advantages of the reservoirs are they keep the engine bay or work area clean by preventing spills, refill an engine when on the road, prevent worry about carrying extra fluid and provide assurance that oil types are not being mixed when drivers need to add a quart.