Automobile manufactures continue to extend out the oil change intervals of their vehicles. A large percentage of new vehicles now come with oil life monitors which help the owner determine when the next oil change is necessary.
Extended oil change intervals conserve resources but have a potential downside. Vehicle owners have come to rely on the vehicle's dash display to tell them everything they need to know. Few are checking their fluid levels between routine service.
In time failure to track oil consumption and monitor that service intervals are adequate can result in a engine with an excessive build up of sludge or other harmful contaminants.