| 摘要 |
A composition of an oil of lubricating viscosity, an antioxidant, an anti-nitration agent, preferably being a hydrocarbylamine phosphate salt and optionally a borated product of an epoxide or the reactive equivalent of an epoxide, provides a desirable lubricant for diesel or natural gas-fueled engines. The composition is substantially free from metals and preferably substantially free from phosphorus. The amount of the antioxidant and the anti-nitration agent are sufficient to reduce the amount of varnish formation in a natural gas engine. |
