The core difference
Grease base oils fall into two categories: mineral oil (refined from petroleum) and synthetic oil (chemically synthesized). They differ significantly in cost, temperature range and service life.
At a glance
| Dimension | Mineral oil | Synthetic oil |
|---|---|---|
| Cost | Low | High (2–10×) |
| Operating temperature | −20°C to 120°C | −60°C to 200°C+ |
| Oxidation stability | Average | Excellent |
| Service life | Short | Long (2–5×) |
| Low-temperature flow | Poor | Good |
| High-temperature evaporation | High | Low |
| Best for | Normal duty | High/low temp, precision, long life |
When to choose mineral oil
- Normal temperature, light load, short service intervals;
- Budget-sensitive, high-volume applications;
- Stable conditions without temperature extremes.
When to choose synthetic oil
- High temperature (>120°C) or low temperature (<−20°C);
- Long-life, low-maintenance requirements (e.g. sealed bearings);
- High speed, precision equipment;
- Low evaporation, low noise requirements.
Conclusion
For normal conditions, mineral oil gives the best value; for high/low temperature, precision and long-life applications, the extra cost of synthetic oil pays back through longer life and lower maintenance. When unsure, provide the operating conditions and let an engineer calculate total cost of ownership.