Can You Mix Synthetic Gear Oil & Regular?by David Dunning
Gear oil is thick (high viscosity), heavy oil that is used to reduce friction, heat transfer and corrosion in units containing gears. Manmade or synthetic gear oils reduce engine wear and can be pumped to critical surfaces faster than regular, mineral (petroleum-based) oils.
Types of Synthetic Gear Oil
There are essentially two different types of synthetic gear oil, polyalphaolefin (poly-alpha-olefin), or PAO and polyalkylene glycol, or PAG. PAO oils are, in fact, enhanced versions of regular mineral oils and can be mixed freely with them.
Indeed, some commercially available gear oils are a mixture of synthetic PAO oil and mineral oil in various proportions. This is a clear indication that synthetic and regular mineral gear oils can be mixed.
PAG oils, on the other hand, are polymers formed by the addition of ethylene or propylene oxide molecular units, or monomers. They offer superior performance when compared with mineral oils, but cannot be mixed with them.
- “Petroleum Fuels Manufacturing Handbook”; Surinder Parkash; 2009
A full-time writer since 2006, David Dunning is a professional freelancer specializing in creative non-fiction. His work has appeared in "Golf Monthly," "Celtic Heritage," "Best of British" and numerous other magazines, as well as in the book "Defining Moments in History." Dunning has a Master of Science in computer science from the University of Kent.