abstract |
A lubricant which is prepared from at least one synthetic ester composition exhibiting thermal and oxidative stability which comprises the reaction product of 3,5,5-trimethyl-1-hexanol and an acid or anhydride; and a lubricant additive package; whereby the incorporation of an antioxidant in the lubricant additive package for the purpose of maintaining oxidative and thermal stability of the crankcase lubricating oil formulation to at least 20 minutes as measured by HPDSC at 220 DEG C., 3.445 MPa air and 0.5 wt. % dioctyl diphenyl amine can be either reduced or eliminated. The synthetic ester composition preferably exhibits the following additional properties: a metals content of 10 ppm or less metals based on the total synthetic ester composition, an ash content of 15 ppm or less ash based on the total synthetic ester composition, a total acid number of 0.05 mg KOH/g or less, and a volume resistivity of at least about 1x1011 ohm cm. |