What do the five different base oil groups mean?

If you have ever used an engine, gear, hydraulic oil or other kind of lubricant, you have probably heard the base oil described as "Group II" or similar. Here we define what a base oil is and what that means, and how it impacts lubricant performance. The definitions provided are both in the sense of manufacturing technology, as well as marketing definitions. We also explore the relative performance parameters of each base oil group, including oxidative stability, solvency, pour point, toxicity and viscosity stability. Become a Lubrication Expert with low-cost industry training: https://lubrication.expert Here at Lubrication Expert we take a first-principles approach to lubricants and greases; helping industry understand lubrication technology and pushing the limits of what is possible. Catch us on Twitter:   / lubricationexp   Catch us on LinkedIn:   / lubrication-expert