A system, a method and a computer program to determine the usability of a lubricant such as, e.g., engine oil, and when to replace the lubricant in a particular engine. The system, method, and computer program are further configured to generate a lubricant discard interval for each engine in, e.g., a company's fleet of vehicles. The system, method, and computer program are configured to generate lubricant discard interval schedule for each of the vehicles in the company's fleet based on the lubricant discard intervals.