The Oxidative Stability test (ASTM D-6186) measures the ability of a lubricant to resist oxidation at elevated temperatures. The test can be conducted on an oil or grease.
Typically reported in ‘minutes’ – The greater the time to exotherm, the better the oxidative stability of the lubricant. Test conditions are the the O2 stability method.
The test conditions:
- 150°C or 175°C
- 3500 kPa oxygen
- 24 hours
- 100ml/min oxygen
Take a look at the article Understanding the role of antioxidants in lubricants