Oil enthusiasts sometimes pontificate about whether detergent oil even contains detergent.  Experts will site that, for engines that need detergent oil, the oil prevents sludge from forming by keeping collections of sludge from sticking together and forming longer chains of sludge within the engine.  It is believed then that before deposits join together to create oil sludge, they would be filtered out by the oil filter.

Non detergent oil may also be an effective gear box oil for certain types of gear boxes currently in use today.  Each engine or gear box should come with recommendations from the company on the best lubricant to use for optimal performance and maintenance.  Engine owners can usually access information about their motors or gear boxes from online sources such as downloadable PDF files or owners manual documents.

In addition to ND oil or non detergent motor oil, there is also HD oil, which is high detergent oil.  Higher amounts of detergent are present in high detergent motor oil as one may suspect.  One way for people to clean the inside of engines is to engage the use of a high detergent oil.  It varies by auto tech, but high detergent oil can be used as a viable solution for some engines.  HD oil is considered to be more gentile on breaking up sludge and less likely to break off sludge in large pieces that would clog oil passages.  What ever your chosen solution for reducing your engine sludge, be advised that every solution has advantages and disadvantages and that to maximize the life of your engine, you need to also maximize your lubrication.