German oil specialist LIQUI MOLY has produced a useful explanation of the differences between mineral, semi-synthetic and fully synthetic oil and why making the correct choice of oil and specification is vital.

Motor oil has developed from a simple lubricant to a high-tech liquid essential for the optimum running of modern engines. At the same time, the number of oil grades and specifications has increased significantly. Oliver Kuhn, deputy head of the oil laboratory at LIQUI MOLY has provided an insight and explains what really matters:

Discussing the different kinds of oils, Oliver says, “Motor oils can be roughly divided into two categories: mineral-based and synthetic oils. Mineral oils are becoming less and less important for cars because they do not offer such high performance. Modern engines demand much more from the oil than old engines. Only synthetic oils can meet these requirements.” He adds, “You can also mix a mineral oil with a synthetic oil. However, such semi-synthetic oils are playing an increasingly smaller role in the market, because their performance is not high enough, due to their mineral content.”

Oliver also explains how synthetic oils can vary. He comments, “There are two different ways in which synthetic oils can be produced. By one of these methods, a so-called PAO oil is obtained at the end. This is the classic synthetic oil as it came on the market in the 1970s. It is chemically very pure and therefore very effective, but also very expensive to produce. With the other approach, the oil is produced by hydro-cracking, which is why these oils are also called HC oils in technical jargon. HC oils are more modern and came up in the 1990s. Today, they offer the best possible performance for all modern engines.”

Oliver then explains about how oils need to meet vehicle manufacturer specifications. He says, “The decisive factor is that the oil meets the specifications which the car manufacturer has set for that model. This is given in the manual of the car, or you can use our free Oil Guide at www.liqui-moly.com. The additive packages in these oils are becoming increasingly important. Today, they are the most important component of a motor oil besides the actual oil. They provide a large part of the motor oil’s performance. With some very modern motor oils, the base oil is hardly more than just the carrier fluid for the additive packages.”