It's hard to say, but clearly synthetics will be the majority of the market place. It depends on the future of engine design and technology. That will continue to drive the additive suppliers/chemists and base oil companies to respond with with better lubricants.
The trend is obviously lower viscosity and the reduction of metallic additives. Beyond that I don't know. Molekule gave you some good examples.
The trend is obviously lower viscosity and the reduction of metallic additives. Beyond that I don't know. Molekule gave you some good examples.